• 제목/요약/키워드: population concentration

검색결과 1,037건 처리시간 0.027초

Impact of Low Concentration Fluoride on Toxification and Biological Traits of Silkworm, Bombyx mori

  • Hosagoudar, S.R.;Yuin, Chen;Yuanxiang, Jin;Manjunatha, H.B.
    • International Journal of Industrial Entomology and Biomaterials
    • /
    • 제9권1호
    • /
    • pp.73-78
    • /
    • 2004
  • The impact of low concentration fluoride on toxification was studied by treating $3^rd$ instar silkworm larvae of Qiufeng${\times}$Baiyu (Fluoride resistant strain) and Jinshong${\times}$Haoyue (Fluoride sensitive strain). The $5^th$ instar silkworm larvae of Zhenong-l, Shu-12, Qiufeng ${\times}$ Baiyu, Chunhua ${\times}$ Qhiushi, Jinshong and Haoyue were fed mulberry leaves treated with sodium fluoride at different concentrations to determine its effect on fecundity. Harmful effects of low concentration fluoride at early instars on growth, development and economic characters of Bombyx mori are related to its resistance. Harmful effect on resistant strain Qiufeng${\times}$Baiyu manifested on prolongation of instar duration of 15 and 6% in 70 ppm, where as the sensitive breed Jinshong${\times}$Haoyue manifested with 100% mortality in 50 ppm. The impact of low concentration fluoride on fecundity resulted in considerable increase in formed eggs (9%) and laid eggs (9%) in Zhenong-l and Shu-12 among treated population over control. The present observations emphasis that fluoride apart from exhibiting harmful effects on silkworm growth and development, however, its low concentration do playa vital role in inducing some positive effect on fecundity and cocoon traits.

Seasonal Distribution, Egg Production and Feeding by the Marine Copepod Calanus sinicus in Asan Bay, Korea

  • Park, Chul
    • Journal of the korean society of oceanography
    • /
    • 제32권2호
    • /
    • pp.85-92
    • /
    • 1997
  • Seasonality in abundance and egg production was investigated for Calanus sinicus in Asan Bay, Korea, and feeding effort was measured in the laboratory condition. Although abundances of this species in this bay showed only one Peak in spring, egg Production showed two peaks, spring and fall, in this bay. Potential of year-round egg Production was also found. Food availability judged by the particulate organic carbon (POC) concentration was usually more than enough in this bay. High egg Production in fall resulted in spring Peak in abundance. But high egg Production in spring did not result in summer or fall Peak in abundance. Low abundances in summer and fall were believed to be the result of long range horizontal migration out to the central Part of the Yellow Sea. The highest average egg Production by the Population of this species was 16.3 eggs female-'day-'. Maximum e99 Production by an individual was 39.0 e99s female$^{-1}$ day$^{-1}$, which yielded 30.7% of specific egg Production rate in terms of body carbon content with the carbon contents of 44.44$^{\mu}$gC and 0.35 $^{\mu}$gC for individual adult female and egg, respectively. Clearance rate (F) measured in the laboratory condition decreased exponentially with the increase of food concentrations, as expected. The asymptote of F was 3.17 ml copepod$^{-1}$ h$^{-1}$. When this value and the minimum concentration of POC measured in the field were applied under the assumption of continuous feeding in the nature, the calculated gross efficient of egg production was 41.6% in case of average egg production of the population. Violation of the assumption of diurnal feeding rhythm and application of the minimum concentration of POC may offset the influence on calculation each other.

  • PDF

인구집단의 비교를 통한 폐금속광산 지역 주민의 카드뮴 노출수준 및 건강영향평가 (Health Impact Assessment for Cadmium Exposure: Comparison of Residents around Abandoned Mines with the General Population)

  • 서정욱;김병권;홍영습
    • 한국환경보건학회지
    • /
    • 제46권3호
    • /
    • pp.297-311
    • /
    • 2020
  • Objective: We compared the level of blood cadmium exposure with health impacts by using data from a survey of residents near an abandoned mine and a national health survey. Methods: For this study, we used data from 7,046 individuals who participated in the Health Effects Survey of Abandoned Metal Mines (AMS, 2008-2011) and 6,871 individuals who participated in the Korea National Health and Nutrition Examination Survey IV-VI (KNHANES, 2008-2013). To evaluate the health impacts, the quartiles (S1 to S4) were classified according to blood cadmium concentration, and then the odds ratios of S2 to S4 over S1 for exceeding the reference values of renal function, blood pressure, and bone density were compared. Similarly, the odds ratio of AMS over KNHANES was confirmed. Results: In the AMS, adjusted for general characteristics, the geometric mean of blood cadmium concentration was 1.34 ㎍/L, which was statistically significantly higher than that of the KNHANES 1.22 ㎍/L (p<0.001). In the integrated data of AMS and KNHANES, the estimated odds ratio of S4 over S1 for exceeding the reference value was found to be 1.70 for serum creatinine, 1.71 for hypertension, and a T-score 2.02 for the tarsal bone. They were all statistically significant. Conclusion: Residents around abandoned metal mines had a higher blood cadmium concentration than the general population, and the odds for exceeding the reference values were higher for some health indicators. Continuous biomonitoring should be conducted for vulnerable areas such as around abandoned metal mines, and measures to reduce cadmium exposure and management of chronic diseases are needed.

양돈장 내의 환경 요인에 따른 내부 유해인자의 변동 모니터링 (Monitoring of Internal Harmful Factors According to Environmental Factors in Pig Farm)

  • 이성원;김효철;서일환
    • 한국농공학회논문집
    • /
    • 제62권1호
    • /
    • pp.105-115
    • /
    • 2020
  • With the decrease of the agricultural population in Korea, the workers who is vulnerable to labor are increasing in agricultural industry because of aging, feminization of population. They are exposed in poor working environment with higher temperature and concentrations of dust, gas. Higher concentration of harmful gas and dust can cause chronic and acute disease to workers depending on exposure intensity and frequency. In order to improve the working environment in the livestock facilities, It is important to secure monitoring data of the thermal environment and the concentration of harmful gases and fine dust. Multi-point measurement was performed to analyze the regional environmental conditions in the pig rooms. When analyzing the working environment, video monitoring was conducted to analyze the concentration changes of ammonia, hydrogen sulfide and fine dust according to worker movement and work type. Ammonia and hydrogen sulfide monitoring result showed 1.5~2 times higher concentrations than other work when working in the pigs living zone, and 2~4 times higher than other work when working to increase the activity of pigs. In the case of fine dust, the result was 1.3 times higher than the worker's exposure standard in a specific work. The concentrations of gases and dusts from pig farms are not of concern for acute poisoning in normal work, but there is a risk of chronic respiratory disease if they are continuously exposed. Accordingly, there is a need for development of work environment monitoring device tailored to workers and preparation of alternatives.

Decomposition of Socioeconomic Inequality in Cardiovascular Disease Prevalence in the Adult Population: A Cohort-based Cross-sectional Study in Northwest Iran

  • Pourfarzi, Farhad;Moghadam, Telma Zahirian;Zandian, Hamed
    • Journal of Preventive Medicine and Public Health
    • /
    • 제55권3호
    • /
    • pp.297-306
    • /
    • 2022
  • Objectives: The incidence of cardiovascular disease (CVD) mortality is increasing in developing countries. This study aimed to decompose the socioeconomic inequality of CVD in Iran. Methods: This cross-sectional population-based study was conducted on 20 519 adults who enrolled in the Ardabil Non-Communicable Disease cohort study. Principal component analysis and multivariable logistic regression were used, respectively, to estimate socioeconomic status and to describe the relationships between CVD prevalence and the explanatory variables. The relative concentration index, concentration curve, and Blinder-Oaxaca decomposition model were used to measure and decompose the socioeconomic inequality. Results: The overall age-adjusted prevalence of CVD was 8.4% in northwest Iran. Multivariable logistic regression showed that older adults, overweight or obese adults, and people with hypertension and diabetes were more likely to have CVD. Moreover, people with low economic status were 38% more likely to have CVD than people with high economic status. The prevalence of CVD was mainly concentrated among the poor (concentration index, -0.077: 95% confidence interval, -0.103 to -0.060), and 78.66% of the gap between the poorest and richest groups was attributed to differences in the distribution of the explanatory variables included in the model. Conclusions: The most important factors affecting inequality in CVD were old age, chronic illness (hypertension and diabetes), marital status, and socioeconomic status. This study documented stark inequality in the prevalence of CVD, wherein the poor were more affected than the rich. Therefore, it is necessary to implement policies to monitor, screen, and control CVD in poor people living in northwest Iran.

도시화의 특징과 불평등도 분석 (Measuring Inequalities in Terms of the Distribution of Urban Population)

  • 박주문
    • 한국인구학
    • /
    • 제18권2호
    • /
    • pp.98-114
    • /
    • 1995
  • 이 연구는 급격한 변동을 겪어 온 한국사회에서 도시화가 어떻게 이루어지고 있고 도시인구의 분포의 측면에서 불평등이 어떻게 이루어져 있는지를 살펴보고 있다. 이 연구결과 1966-70년 사이에 급격히 이루어진 도시화의 성격이 부각되었고, 또 도농간의 성장속도의 차이도 아주 높았음이 드러났다. 무엇보다도 서울의 수위도시성이 명백히 드러났다. 하지만 서울의 수위도시성은 1970년이래 서서히 감소되기 시작했고, 불평등지수인 지니계수를 통해 검증한 결과 1970년에 비해 1990년의 도시인구분포의 불평등성은 완화된 것으로 보이나, 여전히 큰 불평등이 존재하고 있다.

  • PDF

Tacrolimus의 혈중농도측정법 비교 및 간이식환자에서의 집단 약동학 (Comparison of Analytical Methods of Tacrolimus in Plasma and Population Pharmacokinetics in Liver Transplant Recipients)

  • 김은영;강원구;곽혜선
    • 한국임상약학회지
    • /
    • 제18권1호
    • /
    • pp.60-67
    • /
    • 2008
  • This study aimed to compare a microparticle enzyme immunoassay (MEIA) with a liquid chromatography-tandem mass spectrometry (LC/MS/MS) technique for the measurement of tacrolimus concentrations in adult liver transplant recipients, to investigate how the assay choice influenced the population pharmacokinetics of tacrolimus and to identify patient characteristics that affected pharmacokinetic parameters in each assay. Tacrolimus concentrations from 29 liver (n=52 paired-samples) transplant recipients measured by both MEIA and LC/MS/MS were used to evaluate the performance of these methods in the clinical setting. Tacrolimus pharmacokinetics was studied independently using MEIA and LC/MS/MS data in 70 adult patients using a population approach performed with NONMEM. Patient characteristics which influenced pharmacokinetic parameters in each assay were compared. The relation between LC/MS/MS and MEIA measurements was best described by the regression equation MEIA=1.465*LC/MS/MS-1.336 (r=0.91). Multiple linear regression analysis showed significant inverse relationships between assay difference and hematocrit (Hct) (p<0.025) in liver graft recipients. In MEIA, the population estimate of tacrolimus CL/F and apparent volume of distribution (Vd/F) were found to be 10.1 L/h and 226 L, and in LC/MS/MS, 13 L/h and 305 L respectively. Neither patient's age, weight, gender, grafted hepatic weight, albumin concentration, nor markers of liver function influenced tacrolimus CL/F The final model of CL/F was found to be 10.1+(Hct/Hct mean)$^{12.0}$ in MEIA and 13+(1+Hct/578) in LC/MS/MS indicating that CL/F was influenced by hematocrit.

  • PDF

마늘의 농도가 김치 미생물에 미치는 영향 (Effect of Garlic Concentrations on Growth of Microorganisms during Kimchi Fermentation)

  • 조남철;전덕영;신말식;홍윤호;임현숙
    • 한국식품과학회지
    • /
    • 제20권2호
    • /
    • pp.231-235
    • /
    • 1988
  • 마늘의 함량을 각각 0, 1, 2, 4, 6%가 되게하여 김치를 제조하고 $21^{\circ}C$에서 숙성시킨 김치의 숙성 과정중 호기성 세균, 효모 및 종류에 따른 유산균 수의 변화를 조사한 바 호기성 세균수는 숙성 $1{\sim}2$일까지 증식하다 그후 감소하였다. 마늘의 함량이 높은 김치일수록 발효초기에 호기성 세균의 증가폭이 작았으며 1%와 2%마늘 농도에서 큰 차이를 나타냈다. 총 유산균수는 호기성 세균과는 달리 숙성 $1{\sim}2$일까지 증가한 후 발효말기까지 그 수준을 유지하였으며 마늘의 함량이 높은 김치일수록 발효초기의 증가가 켰다. 발효 초기의 유산균의 증가에 주로 관여하는 유산균은 Lac. brevis와 low acid-producing lactobacilli였으며 또한, 발효 기간중 효모수의 변화는 마늘 함량의 변화에 뚜렷하게 나타나지 않았다.

  • PDF

취약계층을 고려한 미세먼지 쉼터 입지 효율성 평가 (Evaluation of the Location Efficiency of Fine Dust Shelters Considering Vulnerable Population in Seoul)

  • 임재권;이혜경
    • 한국BIM학회 논문집
    • /
    • 제12권4호
    • /
    • pp.104-115
    • /
    • 2022
  • Fine Dust in Korea has been classified as a social disaster since 2019 due to continuous increase in concentration of Particulate Matter 10(PM 10) and PM 2.5. The fine dust issue has negative physical and mental impacts, especially on vulnerable population including children and the elderly. Seoul metropolitan government have installed fine dust shelters since 2019. However, there is a lack of research that evaluates spatiotemporal distribution of these facilities. Therefore, the first aim of this study is to find the relationship between PM levels and dust scattering construction sites, or air pollutant emission sites through in depth spatial analyses. The second purpose is to analyze the spatial distribution of PM shelters in Seoul, and to evaluate the location efficiency of them. Kernel density, krigging, and network analyses were conducted, and floating population was considered instead of census data for this research. The reults of network analysis based on the road system showed that Yangcheon-gu, Songpa-gu, Seongbuk-gu, and Dobong-gu were found to need additional fine dust shelters. Also, the results from analyzing the floating population that includes children and the elderly showed that Songpa-gu, Seodaemun-gu, Gangdong-gu, Seocho-gu, and Dongdaemun-gu need more placements of find dust shelters. The results of this study are expected to provide implications for urban planners to enhance find dust shelter placement in urban areas, and vulnerable population issues would be considered in many ways.

수용체 지향의 건강영향평가를 위한 잠재노출 인구수의 산정·활용 가능성 연구 (A Study on the Application of Potential Exposed Population for a Receptor-oriented Health Impact Assessment)

  • 하종식
    • 환경영향평가
    • /
    • 제27권2호
    • /
    • pp.194-202
    • /
    • 2018
  • 국내 법적인 건강영향평가로서 환경영향평가 내 위생 공중보건 항목의 평가는 특정 개발 사업에서 배출되는 유해대기오염물질 배출량 및 주변 주요 지점의 노출농도 산정, 이를 활용한 위해성 평가로 진행되고 있다. 하지만 개발 사업부지 주변의 노출 가능한 인구집단 규모를 고려하지 못하는 등 개발 사업부지 주변의 수용체 특성은 해당 위해성 평가에서 제대로 반영되지 못하고 있다. 본 논문의 목적은 개발 사업부지 주변의 노출 가능한 인구수를 산정 반영한 위해성 평가를 위해 잠재노출 인구수의 산정 및 이를 실제 위생 공중보건 항목 작성 시 활용하는 방안을 제안하는 것이다. 개발 사업부지 주변의 인구수 산정 관련한 국내 자료 현황을 파악하고 이를 고려한 잠재노출 인구수 산정 알고리즘을 제안하였다. 나아가 산업단지 개발 시 유해대기오염물질 배출을 가정한 사례 분석을 수행하였다. 잠재노출 인구수를 활용한 위해성 평가는 인구집단 위해도 개념이 적용되어야 함을 제시하였으며, 향후 연구로 평가결과에 대한 건강영향 여부의 판단기준 설정이 요구됨을 제안하였다. 또한 본 논문의 잠재노출 인구수 산정방법을 통해 개발사업의 입지제한 도구로의 활용가능성을 제안하였다. 이번 논문은 위생 공중보건 항목 작성 시 개발 사업부지 주변의 수용체 특성을 반영한 위해성 평가를 수행하는 방안을 제시했다는 것에 의미가 있다.