• Title/Summary/Keyword: A case control study

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Urinary Bladder Cancer Risk Factors: A Lebanese Case-Control Study

  • Kobeissi, Loulou Hassan;Yassine, Ibrahim Adnan;Jabbour, Michel Elias;Moussa, Mohamad Ahmad;Dhaini, Hassan Rida
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.5
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    • pp.3205-3211
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    • 2013
  • Background: Bladder cancer is the second most incident malignancy among Lebanese men. The purpose of this study was to investigate potential risk factors associated with this observed high incidence. Methods: A case-control study (54 cases and 105 hospital-based controls) was conducted in two major hospitals in Beirut. Cases were randomly selected from patients diagnosed in the period of 2002-2008. Controls were conveniently selected from the same settings. Data were collected using interview questionnaire and blood analysis. Exposure data were collected using a structured face-to-face interview questionnaire. Blood samples were collected to determine N-acetyltransferase1 (NAT1) genotype by PCR-RFLP. Analyses revolved around univariate, bivariate and multivariate logistic regression, along with checks for effect modification. Results: The odds of having bladder cancer among smokers was 1.02 times significantly higher in cases vs. controls. The odds of exposure to occupational diesel or fuel combustion fumes were 4.1 times significantly higher in cases vs controls. The odds of prostate-related morbidity were 5.6 times significantly higher in cases vs controls. Cases and controls showed different clustering patterns of NAT1 alleles. No significant differences between cases and controls were found for consumption of alcohol, coffee, tea, or artificial sweeteners. Conclusions: This is the first case-control study investigating bladder cancer risk factors in the Lebanese context. Results confirmed established risk factors in the literature, particularly smoking and occupational exposure to diesel. The herein observed associations should be used to develop appropriate prevention policies and intervention strategies, in order to control this alarming disease in Lebanon.

A STUDY ON THE SPEED CONTROL OF A LOW SPEED-LONG STROKE MARINE DIESEL ENGINE (저속 장행정 박용디젤기관의 속도제어에 관한 연구)

  • 유영호;하주식
    • Journal of Advanced Marine Engineering and Technology
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    • v.13 no.3
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    • pp.26-36
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    • 1989
  • Recently digital governor system is commonly adapted for the speed control of the marine diesel engine because of too much fluctuation of rpm resulted by the low speed, long stroke, high efficiency and a small number of cylinder of it, and versatile studies on the development of digital governor system are progressed. On this subject the new control method in which the fuel is controlled by feedforwarding the change of load as well as the feedback of angular velocity in case of disregarding the engine dead time and influence of scavenging air was proposed by the authors, and found the method has shown quite a good control performance in comparision to the conventional control method by the simulation using a digital computer for various load change. In this paper the speed control system of a diesel engine is simulated in case of regarding the engine dead time by the proposed method, and also confirm a good control performance of it under even more realistically simulated environment.

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Numerical study of oxygen transport characteristics in lead-bismuth eutectic for gas-phase oxygen control

  • Wang, Chenglong;Zhang, Yan;Zhang, Dalin;Lan, Zhike;Tian, Wenxi;Su, Guanghui;Qiu, Suizheng
    • Nuclear Engineering and Technology
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    • v.53 no.7
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    • pp.2221-2228
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    • 2021
  • One-dimensional oxygen transport relation is indispensable to study the oxygen distribution in the LBE-cooled system with an oxygen control device. In this paper, a numerical research is carried out to study the oxygen transport characteristics in a gas-phase oxygen control device, including the static case and dynamic case. The model of static oxygen control is based on the two-phase VOF model and the results agree well with the theoretical expectation. The model of dynamic oxygen control is simplified and the gas-liquid interface is treated as a free surface boundary with a constant oxygen concentration. The influences of the inlet and interface oxygen concentration, mass flow rate, temperature, and the inlet pipe location on the mass transfer characteristics are discussed. Based on the results, an oxygen mass transport relation considering the temperature dependence and velocity dependence separately is obtained. The relation can be used in a one-dimensional system analysis code to predict the oxygen provided by the oxygen control device, which is an important part of the integral oxygen mass transfer models.

A Comparative Study on the Sizing Systems of the Infants and Children's Swim-suit (유유아 수영복의 치수체계 비교 연구)

  • Yi Kyong-Hwa;Jung Hae Sun
    • Journal of the Korean Society of Clothing and Textiles
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    • v.29 no.1 s.139
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    • pp.1-12
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    • 2005
  • This study was to suggest a feasible sizing system of infants and children's swim-suits. The basic body dimensions were selected after surveying the swimsuit manufacturers. The control dimensions and the secondary dimensions were taken from the 1997 National Anthropometric Survey data for the establishment of the sizing system. While in the current market swimsuit sizes were generally measured by the hip circumference for boys, and the bust and hip circumference for girls, the height was selected in this study as the control dimension because the height is well recognized by the customers and the KS standards specify the height to be the control dimension for infant's and children's wear. In the new sizing system of this study, the height was a control dimension, and hip was selected as a secondary dimension for boys. and bust and hip were selected as secondary dimensions for girls. Conclusively, in this study we suggest 12 sizes in case of 5cm height interval by the KS sizing system and 7 sizes in case of loom height interval by the current market sizing system, based on the height as a control dimension, for a standard swim-suit sizing system for infants and children.

A descriptive study of on-farm biosecurity and management practices during the incursion of porcine epidemic diarrhea into Canadian swine herds, 2014

  • Perri, Amanda M.;Poljak, Zvonimir;Dewey, Cate;Harding, John CS.;O'Sullivan, Terri L.
    • Journal of Veterinary Science
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    • v.21 no.2
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    • pp.25.1-25.16
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    • 2020
  • Porcine epidemic diarrhea virus (PEDV) emerged into Canada in January 2014, primarily affecting sow herds. Subsequent epidemiological analyses suggested contaminated feed was the most likely transmission pathway. The primary objective of this study was to describe general biosecurity and management practices implemented in PEDV-positive sow herds and matched control herds at the time the virus emerged. The secondary objective was to determine if any of these general biosecurity and farm management practices were important in explaining PEDV infection status from January 22, 2014 to March 1, 2014. A case herd was defined as a swine herd with clinical signs and a positive test result for PEDV. A questionnaire was used to a gather 30-day history of herd management practices, animal movements on/off site, feed management practices, semen deliveries and biosecurity practices for case (n = 8) and control (n = 12) herds, primarily located in Ontario. Data was analyzed using descriptive statistics and random forests (RFs). Case herds were larger in size than control herds. Case herds had more animal movements and non-staff movements onto the site. Also, case herds had higher quantities of pigs delivered, feed deliveries and semen deliveries on-site. The biosecurity practices of case herds were considered more rigorous based on herd management, feed deliveries, transportation and truck driver practices than control herds. The RF model found that the most important variables for predicting herd status were related to herd size and feed management variables. Nonetheless, predictive accuracy of the final RF model was 72%.

A Case -Control Study on Dietary and Other Factors Related to Stomach Cancer Incidence (위암 발생의 식이 및 관련요인에 대한 환자군-대조군 연구)

  • 염필영
    • Journal of Nutrition and Health
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    • v.31 no.1
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    • pp.62-71
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    • 1998
  • As stomach cancer is very prevalent in Koreans, various factors, especially dietary factors, related to stomach cancer incidence were examined in a case-control study. The study population consisted of 105 individual s diagnosed for stomach cancer in two general hospitals and 124 control subjects, matched for age and sex, in Seoul. Data for general characteristics, family history, smoking and alcohol consumption, personality , dietary habits and food preference were obtained by self-administered questionnaire and personal interview. Heredity was found to be one of the most important factors causing stomach cancer. In addition, genetic inheritance tended to differ between the sexes. The male patients showed significantly higher incidence of their father's relatives than mother's relatives but the female patients showed higher incidence of their mother's relatives that father's relatives. Smoking was significantly related to stomach cancer. It was also found that the cases drank alcohol more frequently and in much greater quantity than the controls. Personality was related to the incidence of stomach cancer. The cases tended to be more sensitive , impatient, and anxious to do things quickly. With regards to dietary habits, the male cases had meals significantly more irregularly than the male controls. The relative risk of preferencefor salty food and ramen showed to be significantly very high. The male cases consumed carbonated beverages and instant foods, low intake of green yellow vegetables, smoking of cigarettes and drinking of alcohol may contribute to the risk of stomach cancer.

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A Study of Temporary Permission Delegation In Role-Based Access Control Policy (역할-기반 접근 제어 정책에서 일시적 권한 위임에 관한 연구)

  • Na, Sang-Yeob
    • Journal of the Korea Computer Industry Society
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    • v.10 no.1
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    • pp.21-28
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    • 2009
  • Role-Based Access Control Policy has a role hierarchies in which a higher case role can perform permissions of a lower case role. However, it is necessary for a lower case role to perform a higher case role's permission, which is not allowed to a lower case role, basically. In this paper propose a temporary permission delegation method. As the result of a temporary permission delegation, junior roles can perform senior roles' permissions in a dedicated interval.

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Nutrient Intake and Breast Cancer Risk in Korean Women : A case - control study

  • Do, Min-Hee;Lee, Sang-Sun;Jung, Pa-Jong;Lee, Min-Hyuk
    • Nutritional Sciences
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    • v.6 no.2
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    • pp.106-112
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    • 2003
  • To investigate the association between breast cancer risk and nutrient intake in Korean women, a case-control study was carried out. Incident cases (n=224) were identified through cancer biopsy between february 1999 and December 2000 at two university hospitals in Seoul. Hospital-based controls (n=250) were selected from patients in the same hospitals, during the same periods. food intake was investigated with semi-quantitative food frequency questionnaire (98 items) by a trained dietitian. Subjects were asked to indicate the average intake, for a 12-month period of three years prior to the baseline phase. In this study, no apparent association was found between fat intake level and breast cancer risk. High fiber intake showed a significant inverse association only among premenopausal women. In terms of antioxidant vitamins, $\beta$-carotene and vitamin C among premenopausal women and vitamin C intake among postmenopausal women was significantly associated with a decreasing risk of breast cancer. A protective effect of high calcium consumption was observed among postmenopausal women. In conclusion, our findings support epidemiological evidence that antioxidant vitamin intake could lower the breast cancer risk in Korea.

Performance Improvement of the Inverse Modeling using Adaptive Line Enhancer (적응 선형 증진기를 이용한 인버스 모델링의 성능향상)

  • Kim, Heung-Sub;Hong, Jin-Seok;Son, Dong-Gu;Shin, Jun;Oh, Jae-Eung
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1996.11a
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    • pp.267-271
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    • 1996
  • In this study, performance improvement of the inverse modeling as the on-line control method for the estimation, control experiment is performed. As the modeling errors is occurred in duct system arbitrarily, a case using the filtered-x LMS algorithm only as the control method, a case using tile inverse modeling method only and a case using the inverse modeling with the adaptive line enhancer are compared. The estimation errors between real secondary path transfer functions and the estimated and the control performances of primary noises with these estimated transfer functions are compared.

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