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A Study on the Settling of Suspended Material in 4 weirs of the Nakdong River (낙동강 본류 4개보에서 부유물질 침강에 관한 연구)

  • Lee, Jaesoon;Han, Gyusung;Kwon, Bomin;Choi, Kwangsoon
    • Proceedings of the Korea Water Resources Association Conference
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    • 2018.05a
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    • pp.488-488
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    • 2018
  • 본 연구는 보 구간에서 조류와 조류 발생원인 물질의 거동해석 및 조류예측모델의 입력 자료로 활용하기 위하여 부유물질의 침강량과 침강속도를 조사하였다. 낙동강 수계 4개보(달성보, 강정고령보, 합천창녕보, 창녕함안보)를 대상으로 2017년 6월, 7월, 11월, 12월에 조사하였으며, Sediment trap을 이용하여 포집한 침강물질에 대해 seston, POC, PON, POP, Chl-a, Pheo-a의 침강량, 침강속도 및 물질의 함량비를 분석하였다. 조사기간 동안 낙동강수계 4개보 지점에서 seston, POC, PON, POP, Chl-a, Pheo-a 의 침강량은 각각 $322.7{\sim}58,011.5mg/m^2/day$, $33.8{\sim}1,127.2mg/m^2/day$, $4.2{\sim}150.6mg/m^2/day$, $0.667{\sim}10.634mg/m^2/day$, $0.3{\sim}18.7mg/m^2/day$, $0.3{\sim}14.7mg/m^2/day$의 범위로 나타났으며, seston, POC, PN, PP, Chl-a의 침강속도는 각각 0.02~1.46m/day, 0.02~1.36m/day, 0.03~3.18m/day, 0.01~1.18m/day, 0.02~0.60 m/day의 범위로 나타났다. 조사기간 동안 4개보 지점의 평균 침강속도는 seston 0.94m/day, POC 0.44m/day, PON 0.52m/day, POP 0.21m/day, Chl-a 0.22m/day로 보 건설 전인 2004년도 낙동강 본류 지점에서의 침강속도(seston 14.54 m/day, POC 18.32m/day, PON 1.64m/day, POP 5.96m/day, Chl-a 0.29m/day)에 비해 적은 것으로 나타났다. 한편 활성을 잃은 식물플랑크톤을 나타내는 Pheo-a의 농도와 살아있는 식물플랑크톤의 현존량의 지표 Chl-a의 농도 비교결과 죽거나 활성을 잃은 식물플랑크톤의 양이 평균 1.5배 많은 것으로 나타났다. 조사기간 동안 4개 보 지점의 Sediment trap 포집된 침강물 내 C:N비는 2.0~7.4 범위로, N;P비는 14.2~52.5 범위로, C/Chl-a비는 14.4~253.3의 범위로 나타났다. 일반적으로 조류의 C/Chl-a 비가 40으로 볼 때 본 연구에서 조사된 보 지점에서의 침강물은 외부로부터 유입된 유기물이 많은 것으로 판단된다. 본 연구에서는 조류의 침강속도는 조류의 종을 구분하지 않은 총 조류에 대한 것으로, 향후 보 구간에서 종 조성을 고려한 조류예측 모델을 향상시키기 위해서는 조류 종별에 대한 침강속도에 대한 연구할 필요가 있다.

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Perceived oral malodor and need for dental care among visitors receiving dental prophylaxis (치면세마 실습실 방문자의 구취에 대한 주관적 자각정도와 관심)

  • Jeong, Mi-Kyoung;Jang, Gye-Won;Kang, Yong-Ju
    • Journal of Korean society of Dental Hygiene
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    • v.11 no.6
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    • pp.843-852
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    • 2011
  • Objectives : The aims of the study were to examine perceived oral malodor and self-reported need for oral and dental care among patients receiving oral prophylaxis services and provide guidelines for developing educational programs(toothbrushing method and tongue cleaning) for oral hygiene and oral malodor prevention. Methods : The survey was administered to a sample of 462 receiving voluntary oral prophylaxis service in a dental laboratory at the J School of Public Health in Korea. The subjects were asked a range of questions related to the degrees of perceived oral malodor and concern for oral health status, as well as their demographic information and need for oral and dental treatment. Univariate analyses using Chi-square and T-test with a P-value of .05 were performed using SPSS Version 12.0 for Windows. Results : 1. Male participants reported "moderately concerned for bad breath and smell" and "I don't care bad breath and smell" 39.1% and 26.2% respectively, while more female participants were concerned for oral malodor. "moderately concerned for malodor" and" highly concerned for malodor" 41.1% and 28.5%(p<.05). a significant difference among age groups was found. 19% of young adults (less than or equal to 29 years of age) reported "highly concerned for bad breath and smell" while 36.4% of older adults (greater than or equal to 50 years of age) reported "highly concerned for bad breath and smell"(p<.05). 2. 12 non-smoking participants (3.7%) and 15 smoking participants (10.8%) reported that they have perceived bad breadth and smell (p<.05). 3. Smoking participants reported a higher degree of need for oral malodor treatment than that of non-smoking participants 88.5% and 82% respectively(p<.05). 4. The participants who did regular toothbrushing more than 3 times a day reported "no malodor", 77 % as compared to 66.7% of the participants who did regular toothbrushing 2 times a day. Toothbrushing 2 times a day reported either "moderate malodor" or "sever malodor"(p<.01). Participants with more frequent toothbrushing reported less oral and breath odor as compared participants with less frequent toothbrushing. Conclusions : The study suggested that there is a need to oral prophylaxis for prevention and toothbrushing and tongue cleaning method oral malodor care and oral health status.

Breast Cancer Recurrence According to Molecular Subtype

  • Shim, Hee Jin;Kim, Sung Hun;Kang, Bong Joo;Choi, Byung Gil;Kim, Hyeon Sook;Cha, Eun Suk;Song, Byung Joo
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.14
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    • pp.5539-5544
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    • 2014
  • Background: To evaluate the location of tumor relapse and imaging modality for detection according to the breast cancer subtype: luminal A, luminal B, HER2 positive luminal B, nonluminal HER2 positive, and triple negative. Materials and Methods: A total of 1244 patients with breast cancer with known estrogen receptor (ER), progesterone receptor (PR), Ki-67 and human epidermal growth factor receptor 2 (HER2), who underwent breast surgery from 2009 to 2012 were analyzed. Patients were classified into the following categories: luminal A (n=458), luminal B (n=241), HER2 positive luminal B (n=227), nonluminal HER2 positive (n=145) and triple negative (n=173). A total of 105 cases of relapse were detected in 102 patients: locoregional recurrence (n=46), recurrence in the contralateral breast (n=28) and distant metastasis (n=31). Comparison of proportions was used to determine the difference between subtypes. Results: Relapse rates by subtypes are as follows: luminal A 23 of 458 (5.02%), luminal B 19 of 241(7.88%), HER2 positive luminal B 15 of 227 (6.61%), nonluminal HER2 postive 19 of 145 (13.10%) and triple negative 29 of 173(16.76%). Luminal A tumors had the lowest rate of recurrence and had significantly lower recurrence rate in comparison with nonluminal HER2 postive (p=0.0017) and triple negative subtypes (p<0.0001). Compared with all other subtypes except nonluminal HER2 positive, triple negative tumors had the highest rate of tumor recurrence (p<0.01). Triple negatives were most likely to develop contralateral recurrence against all subtypes (p<0.05). Detection rate of locoregional and contralateral tumor recurrence were 28.3% on mammography (n=17/60). Conclusions: Luminal A tumors are associated with a low risk of recurrence while triple negative lesions have a high risk. In case of triple negative tumors, the contralateral breast has much more recurrence as compared with all other subtype. In terms of detection rates, breast USG was the best modality for detecting tumor recurrence, compared with other modalities (p<0.05). Subtyping of breast tumors using a molecular gene expression panel can identify patients who have increased risk of recurrence and allow prediction of locations of tumor recurrence for each subtype.

A Model on the Determinants of Visual Preference at Golf courses (경관의 선호도 결정인자 모형 -골프장을 배경으로-)

  • 서주환;이철민;맹상빈
    • Journal of the Korean Institute of Landscape Architecture
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    • v.29 no.1
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    • pp.1-10
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    • 2001
  • The purpose of this thesis is to classify landscape-type of golf course, and t provide a better understanding of landscape of existing golf courses, seek a developed method for landscape, and other useful knowledge. In order to classify landscape type of the golf course, and analyze the preference for the determinants, we have selected 4 golf courses in Yongin, Kyonggi Province. The analysis in this study shows that a variable, 'familiarity' is the most potent influence of visual preference, (Sig 0.01), and it can be divided into five classes of landscape-type in golf course. More specifically, we conducted the analysis of the image of views and visual preference to bring out major factors which could decide visual preference in golf courses. The results between visual preference and physical variable are as follows; 1. It implies that a factor for a image of the view in golf course is analyzed by 4 districts from factor 1 to factor 4. An ability explaining those factors in the whole of variable quantity is 51.742%, implying factors for the image of the scene in golf courses are appeared as familiarity, changeableness, spaciousness, and naturalness. Among those factors, since familiarity(C.V.; 26.783%) and changeableness(C.V.; 112.200%) took high rank, this represents the fact that familiarity or changeableness highly affects the forming of image. 2. Defending on degree of image ability in golf course, we could classify as five types such as Type I, Type II, Type II, Type IV, and Type V. 3. As a result of calculating type of factor score, Type I had the lowest ranking in naturalness, and rather lower than others such as organization and spaciousness. The II is a top-ranked one in familiarity and naturalness, while it has the lowest ranking in spaciousness. Type III has the highest ranking in organization and preference. Type IV is the lowest-ranked one in familiarity and preference. Type IV is the lowest-ranked one is familiarity and preference. Type V has the highest ranking in spaciousness, but the lowest ranking in organization. 4. As a result of preference, Type III, Type II, Type V, Type I, and Type IV come out in order. That water-seen place type charges the highest rank shows the importance of changeable materials. 5. These factors-familiarity, organization, spaciousness and naturalness- are the major materials of the scene of view in golf courses. The possibility of how to use those for designing and making enhanced golf courses should be reinvestigated through these factors. Especially, it is acknowledged that the duction of changeableness, which is not mentioned in the study of informational approach, is much stimulating for the designing use. A further research on this theme should be made in the future, not limiting to the golf courses in Yongin.

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Firefighting and Cancer: A Meta-analysis of Cohort Studies in the Context of Cancer Hazard Identification

  • Nathan L. DeBono;Robert D. Daniels ;Laura E. Beane Freeman ;Judith M. Graber ;Johnni Hansen ;Lauren R. Teras ;Tim Driscoll ;Kristina Kjaerheim;Paul A. Demers ;Deborah C. Glass;David Kriebel;Tracy L. Kirkham;Roland Wedekind;Adalberto M. Filho;Leslie Stayner ;Mary K. Schubauer-Berigan
    • Safety and Health at Work
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    • v.14 no.2
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    • pp.141-152
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    • 2023
  • Objective: We performed a meta-analysis of epidemiological results for the association between occupational exposure as a firefighter and cancer as part of the broader evidence synthesis work of the IARC Monographs program. Methods: A systematic literature search was conducted to identify cohort studies of firefighters followed for cancer incidence and mortality. Studies were evaluated for the influence of key biases on results. Random-effects meta-analysis models were used to estimate the association between ever-employment and duration of employment as a firefighter and risk of 12 selected cancers. The impact of bias was explored in sensitivity analyses. Results: Among the 16 included cancer incidence studies, the estimated meta-rate ratio, 95% confidence interval (CI), and heterogeneity statistic (I2) for ever-employment as a career firefighter compared mostly to general populations were 1.58 (1.14-2.20, 8%) for mesothelioma, 1.16 (1.08-1.26, 0%) for bladder cancer, 1.21 (1.12-1.32, 81%) for prostate cancer, 1.37 (1.03-1.82, 56%) for testicular cancer, 1.19 (1.07-1.32, 37%) for colon cancer, 1.36 (1.15-1.62, 83%) for melanoma, 1.12 (1.01-1.25, 0%) for non-Hodgkin lymphoma, 1.28 (1.02-1.61, 40%) for thyroid cancer, and 1.09 (0.92-1.29, 55%) for kidney cancer. Ever-employment as a firefighter was not positively associated with lung, nervous system, or stomach cancer. Results for mesothelioma and bladder cancer exhibited low heterogeneity and were largely robust across sensitivity analyses. Conclusions: There is epidemiological evidence to support a causal relationship between occupational exposure as a firefighter and certain cancers. Challenges persist in the body of evidence related to the quality of exposure assessment, confounding, and medical surveillance bias.

A study on some high school boys' practice of oral health control(around toothbrushing) and knowledge of decay and preferred taste (일부 남고생의 간식 선호맛과 구강관리실천(잇솔질 중심) 및 우식지식도 조사)

  • Choi, Yun-Hwa
    • Journal of Korean society of Dental Hygiene
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    • v.10 no.2
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    • pp.361-374
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    • 2010
  • Objectives : The purpose of this study was to provide some basic data for effective prevention and oral health education for oral health. For that purpose, a self-administered questionnaire was distributed to the boys of three high schools in Gyeonggi Province. Methods : The questionnaire consisted of items about the practice of oral health control and knowledge of decay according to grade, number of snacking, preferred taste, and toothbrushing. Total 487 questionnaires were put to analysis using the SPSS WIN 13.0 program. Results : 1. The biggest number of the boys brushed their teeth twice a day. The 10th graders brushed teeth three times a day, and the 11th and 12th graders tended to brush teeth twice a day(${\chi}^2$=18.21, p<.05). 2. As for the way of toothbrushing, 39.0% of the boys said they brushed teeth the way they felt like, being followed by those who said they brushed teeth turning the toothbrush up and down and brushing both the teeth and gums(32.6%). As for the number of snacking, those who had snacks three times a day or more brushed teeth turning the toothbrush up and down and brushing both the teeth and gums. Those who hardly had snacks more tended to brush teeth the way they felt like than those who had snacks(${\chi}^2$=21.28, p<.05). And as for preferred tastes, those who preferred a sweet and salty taste more tended to brush teeth the way they felt like than others. And those who preferred a hot taste brushed teeth turning the toothbrush up and down and brushing both the teeth and gums(${\chi}^2$=26.85, p<.01). 3. The respondents' percentage of correct answers for 'Decay is caused by bacteria' was 81.5%. Those who preferred a hot taste recorded the highest percentage of correct answers(${\chi}^2$=21.95, p<.00). 4. Their percentage of correct answers for 'Decay is accompanied by pain from the beginning' was 78.2%. The 12th graders had the highest rate of correct answers, and the 11th graders had the highest rate of wrong answers(${\chi}^2$=11.56, p<.00). 5. Their percentage of correct answers for 'Fluorine is helpful to the prevention of decay' was 75.4%. Those who hardly had snacks recorded the highest rate of correct answers(${\chi}^2$=10.05, p<.02). 6. Their percentage of correct answers for 'There is a way to supply fluorine into the waterworks' was 29.2%, which means the percentage of wrong answers was much higher. The percentage of wrong answers was the highest in the 11th grade(${\chi}^2$=7.06, p<.03). 7. The respondents' mean scores of knowledge of decay were 13.15 of total 18. While the 12th graders showed the highest level of knowledge of decay, the 11th graders were lower in the level of knowledge of decay than the other graders. And there were significant differences(F=5.41, p<.01) according to grade with no such differences according to the number of snacking and preferred taste. Conclusions : Oral health education should be applied to the boys all through their life to have a great effect, and it is important that they should always put the oral health education into practice to be a successful education.

Evaluation of Radiation Exposure to Nurse on Nuclear Medicine Examination by Use Radioisotope (방사성 동위원소를 이용한 핵의학과 검사에서 병동 간호사의 방사선 피폭선량 평가)

  • Jeong, Jae Hoon;Lee, Chung Wun;You, Yeon Wook;Seo, Yeong Deok;Choi, Ho Yong;Kim, Yun Cheol;Kim, Yong Geun;Won, Woo Jae
    • The Korean Journal of Nuclear Medicine Technology
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    • v.21 no.1
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    • pp.44-49
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    • 2017
  • Purpose Radiation exposure management has been strictly regulated for the radiation workers, but there are only a few studies on potential risk of radiation exposure to non-radiation workers, especially nurses in a general ward. The present study aimed to estimate the exact total exposure of the nurse in a general ward by close contact with the patient undergoing nuclear medicine examinations. Materials and Methods Radiation exposure rate was determined by using thermoluminescent dosimeter (TLD) and optical simulated luminescence (OSL) in 14 nurses in a general ward from October 2015 to June 2016. External radiation rate was measured immediately after injection and examination at skin surface, and 50 cm and 1 m distance from 50 patients (PET/CT 20 pts; Bone scan 20 pts; Myocardial SPECT 10 pts). After measurement, effective half-life, and total radiation exposure expected in nurses were calculated. Then, expected total exposure was compared with total exposures actually measured in nurses by TLD and OSL. Results Mean and maximum amount of radiation exposure of 14 nurses in a general ward were 0.01 and 0.02 mSv, respectively in each measuring period. External radiation rate after injection at skin surface, 0.5 m and 1 m distance from patients was as following; $376.0{\pm}25.2$, $88.1{\pm}8.2$ and $29.0{\pm}5.8{\mu}Sv/hr$, respectively in PET/CT; $206.7{\pm}56.6$, $23.1{\pm}4.4$ and $10.1{\pm}1.4{\mu}Sv/hr$, respectively in bone scan; $22.5{\pm}2.6$, $2.4{\pm}0.7$ and $0.9{\pm}0.2{\mu}Sv/hr$, respectively in myocardial SPECT. After examination, external radiation rate at skin surface, 0.5 m and 1 m distance from patients was decreased as following; $165.3{\pm}22.1$, $38.7{\pm}5.9$ and $12.4{\pm}2.5{\mu}Sv/hr$, respectively in PET/CT; $32.1{\pm}8.7$, $6.2{\pm}1.1$, $2.8{\pm}0.6$, respectively in bone scan; $14.0{\pm}1.2$, $2.1{\pm}0.3$, $0.8{\pm}0.2{\mu}Sv/hr$, respectively in myocardial SPECT. Based upon the results, an effective half-life was calculated, and at 30 minutes after examination the time to reach normal dose limit in 'Nuclear Safety Act' was calculated conservatively without considering a half-life. In oder of distance (at skin surface, 0.5 m and 1 m distance from patients), it was 7.9, 34.1 and 106.8 hr, respectively in PET/CT; 40.4, 199.5 and 451.1 hr, respectively in bone scan, 62.5, 519.3 and 1313.6 hr, respectively in myocardial SPECT. Conclusion Radiation exposure rate may differ slightly depending on the work process and the environment in a general ward. Exposure rate was measured at step in the general examination procedure and it made our results more reliable. Our results clearly showed that total amount of radiation exposure caused by residual radioactive isotope in the patient body was neglectable, even comparing with the natural radiation exposure. In conclusion, nurses in a general ward were much less exposed than the normal dose limit, and the effects of exposure by contacting patients undergoing nuclear medicine examination was ignorable.

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A study on the actual condition of dental clinic use of the out patient (일부 외래환자의 치과의원 이용실태에 관한 연구)

  • Han, Se-Young;Han, Soo-Youn
    • Journal of Korean society of Dental Hygiene
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    • v.10 no.4
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    • pp.635-644
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    • 2010
  • Objectives : The purpose of this study was to analyze and investigate the effecting factors on the actual condition of dental clinic use of the out patient. Methods : In oder to achieve this purpose, A survey for 302 patients in 6 participating dental clinics located in Daejeon metropolitan city from May 01 to May 30, 2010. The result of this study was as follows. Results : 1. The duration of dental clinic use was reflected in 36.1% of the under 1 year, 34.1% of over 2 years, and 29.8% of over 1 ~ under 2 years in order. Especially, the higher the duration of over 2 years the higher the age was, on married group had a significance. 2. The type of medical examination for samples was 27.6% of periodontal, 26.5% of conservative, 17.2% of prosthodontics, 10.9% of implant, and 7.9% of preventive in order. Especially, the male group the more the prosthodontics, implant had a significance. the higher the monthly income, on married group, the more the periodontal, prosthodontics and implant had a significance. 3. The motive of dental clinic selection was 38.4% of acquaintances' inducement, 33.4% of the superb treatment, 15.6% of easy convenience, and 7.0% of friendliness staff in order. Especially, male group the more the easy convenience, superb treatment, friendliness staff had a significance. 4. The mean of transportation in order to visit a dental clinic was 38.7% of public transportation, 37.5% of the own car, 23.8% of others in order. Especially, there was a highly significant difference on the public transportation in female, the lower education level, lower monthly income, and medical protection group. 5. The duration of time required of dental clinic reflected in 80.1% of the under 30 minute, 16.3% of over 30 minute~under 1 hour, and 3.6% of over 1 hour in order. Especially, the higher the treatment satisfaction, the dissatisfaction the higher the duration of time required under 30 minute had a significance. Conclusions : These results indicate that as medical services upgrade and get more varied, the expectation of medical quality also increases. It is thus considered that the revitalization of this hospital's management strategy can be achieved by providing highly developed medical services, and, more importantly, by better understanding the actual conditions of dental clinic use by the patients themselves.

A Study on Foreigner Preferences and Sensory Characteristics of Kimchi Fermented for Different Periods (김치의 숙성기간에 따른 외국인의 관능적 선호도 조사)

  • Jung, Eun-Hee;Ryu, Jung-Pyo;Lee, Sang-Il
    • Journal of the Korean Society of Food Culture
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    • v.27 no.4
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    • pp.346-353
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    • 2012
  • This study was designed to investigate foreigner preferences for the sensory characteristics of kimchi with different fermentation periods. After fermentation in a 5 freezer for 1, 7, and 15 days, Red Chinese Cabbage Kimchi, White Chinese Cabbage Kimchi, Kkakdugi, Chonggak Kimchi, Cucumber Kimchi, Green Onion Kimchi, and Mustard Kimchi were served to the respondents. The respondents had resided in Seoul and Kyunggi province for 3 years or less, and were from Asia, Europe, and the Middle East. Most respondents (62.9%) consumed a Korean meal daily, and 45% of all respondents reported eating kimchi 3 or 4 times a week. As a result, it can be said that foreigners residing in Korea preferred to eat kimchi as a side dish. Based on the respondents answers, we were able to determine the relative popularity of the different types of kimchi. They were, from most popular to least popular, Red Chinese Cabbage Kimchi, Kkakdugi Kimchi, Cucumber Kimchi, White Chinese Cabbage Kimchi, Chonggak Kimchi, Green Onion Kimchi, and Mustard Kimchi. Among those fermented for 1 day, Cucumber Kimchi was most preferred for its. When evaluating the overall preference of Kimchi, the best was in the order of Chinese cabbage (red)>Kkakdugi>Cucumber>Chinese cabbage (white)>Chonggak>Green onion>Mustard Kimchi. For 1 day in a fermented period, Cucumber Kimchi had the most preferred taste (5.76), appearance (5.66), odor (5.89), and texture (5.70). However, Cucumber Kimchi was least popular after 15 days of fermentation (p<0.01). The most preferred Kimchi after 15 days of fermentation was Red Chinese Cabbage Kimchi. Among the kimchi fermented for 7 days, White Chinese Cabbage Kimchi was most preferred. While foreigners indicated that they were satisfied with all the types of kimchi fermented for 1 day and 15 days, they were not satisfied with any of the kimchi fermented for 7 days, save for the White Chinese Cabbage Kimchi. Kkakdugi Kimchi had very high satisfaction scores for appearance, but low scores in taste. On the other hand, Chinese Cabbage Kimchi had low scores in odor (5.02-5.29), but high in texture (5.37-5.62) and taste (4.80-5.30), which are not factors sensitive to a change in acidity. These results showed that foreigners were generally satisfied with Kimchi, but became less satisfied as the Kimchi ripened. Most foreigners were not satisfied with the types of Kimchi that had a strong flavor. Chinese Cabbage Kimchi became the least sour after fermentation, and Cucumber Kimchi became most sour after fermentation.

Relationship between Genetic Polymorphisms in MTHFR (C677T, A1298C and their Haplotypes) and the Incidence Of Breast Cancer among Jordanian Females - Case-Control Study

  • Awwad, Nemah;Yousef, Al-Motassem;Abuhaliema, Ali;Abdalla, Ihab;Yousef, Muhammad
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.12
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    • pp.5007-5011
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    • 2015
  • Background: Breast cancer is a major cause of morbidity and mortality in Jordan and worldwide. Abnormality of DNA methylation is a possible mechanism for the development of cancer. Methylenetetrahydrofolate reductase (MTHFR) is involved in DNA methylation. Our aim was to study the association between genetic polymorphisms of MTHFR at two sites (C677T and A1298C) and their haplotypes and the risk of breast cancer among Jordanian females. Materials and Methods: A case-control study involving 150 breast cancer cases and 150 controls was conducted. Controls were age-matched to cases. Polymerase chain reaction/restriction fragment length polymorphism (PCR-RFLP) technique and sequencing were conducted to determine the genotypes. Results: There was a significant difference in genotype frequency of C677T in the 41-60 year age category [cases: CC (37.4%), CT (49.5%) and TT (13.2%); controls: CC (56.3%), CT (35.6%) and TT (8%), p= 0.04; $OR_{TT\;vs.\;CC}$: 2.5, 95% CI: (0.9-6.9); $OR_{at\;least\;on\;T$: 2.1, 95%CI: (1.2-3.9)]. There was no significant difference in genotype frequency of A1298C between cases and controls [cases: AA (46.6%), AC (41.8%) and CC (11.6%); controls: AA (43%), AC (47.4%) and CC (9.6%); p= 0.6]. There was a significant difference of MTHFR genetic polymorphism haplotypes among breast cancer cases and controls [cases/control: CA: 38.3/45.4%; CC: 28.9/25.2%; TA: 29.2/21; TC: 3.6/8.3; p value= 0.01; $OR_{TA\;vs.\;CA}=1.6$; 95% CI (1.1-2.5); p= 0.02]. Conclusions: Genetic polymorphism of MTHFR C677T may modulate the risk of breast cancer especially in the 41-60 year age group. Additionally, TA haplotype amends the risk of breast cancer. Future studies with a larger sample size are needed to validate the role of MTHFR genetic polymorphisms in breast cancer.