• Journal of the Korean Association of Geographic Information Studies
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• v.19 no.4
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• pp.118-129
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• 2016

Many epidemiological studies, relying on administrative air pollution monitoring data, have reported the association between particulate matter ($PM_{10}$) air pollution and human health. These monitoring data were collected at a limited number of fixed sites, whereas government-generated health data are aggregated at the area level. To link these two data types for assessing health effects, it is necessary to estimate area-level concentrations of $PM_{10}$. In this study, we estimated district (Gu)-level $PM_{10}$ concentrations using a previously developed pointwise exposure prediction model for $PM_{10}$ and three types of point locations in Seoul, Korea. These points included 16,230 centroids of the largest census output residential areas, 422 community service centers, and 610 centroids on the 1km grid. After creating three types of points, we predicted $PM_{10}$ annual average concentrations at all locations and calculated Gu averages of predicted $PM_{10}$ concentrations as representative Gu-estimates. Then, we compared estimates to each other and to measurements. Prediction-based Gu-level estimates showed higher correlations with measurement-based estimates as prediction locations became more population representative ($R^2=0.06-0.59$). Among the three estimates, grid-based estimates gave lowest correlations compared to the other two(0.35-0.47). This study provides an approach for estimating area-level air pollution concentrations and assesses air pollution health effects using national-scale administrative health data.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.2
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• pp.719-722
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• 2016

Background: Cholangiocarcinoma (CCA) is a serious health problem in Thailand, particularly in northeastern and northern regions, but epidemiological studies are scarce and the spatial distribution of CCA remains to be determined. A database for the population at risk is required for monitoring, surveillance and organization of home health care. This study aim was to geo-visually display the distribution of CCA in northeast Thailand, using a geographic information system and Google Earth. Materials and Methods: A cross-sectional survey was carried out in 9 sub-districts and 133 villages in Chum Phuang district, Nakhon Ratchasima province during June and October 2015. Data on demography, and the population at risk for CCA were combined with the points of villages, sub-district boundaries, district boundaries, and points of hospitals in districts, then fed into a geographical information system. After the conversion, all of the data were imported into Google Earth for geo-visualization. Results: A total of 11,960 from 83,096 population were included in this study. Females and male were 52.5%, and 47.8%, the age group 41-50 years old 33.3%. Individual risk for CCA was identifed and classified by using the Korat CCA verbal screening test as low (92.8%), followed by high risk (6.74%), and no (0.49%), respectively. Gender ($X^2$-test=1143.63, p-value= 0.001), age group ($X^2$-test==211.36, p-value=0.0001), and sub-district ($X^2$-test=1471.858, p-value=0.0001) were significantly associated with CCA risk. Spatial distribution of the population at risk for CCA in Chum Phuang district was viewed with Google Earth. Geo-visual display followed Layer 1: District, Layer 2: Sub-district, Layer 3: Number of low risk in village, Layer 4: Number of high risk in village, and Layer 5: Hospital in Chum Phuang District and their related catchment areas. Conclusions: We present the first risk geo-visual display of CCA in this rural community, which is important for spatial targeting of control efforts. Risk appears to be strongly associated with gender, age group, and sub-district. Therefor, spatial distribution is suitable for the use in the further monitoring, surveillance, and home health care for CCA.

• Journal of Environmental Science International
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• v.24 no.7
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• pp.875-882
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• 2015

In 2013, International Agency for Research on Cancer (IARC) concluded that outdoor air pollution is carcinogenic to humans, with the particulate matter component of air pollution most closely associated with sufficient evidence of increased cancer incidence by exposure to particulate matter component of air pollution. Motor vehicles are one of a major emission sources of fine particle ($PM_{2.5}$) in urban areas. A large number of epidemiological studies have reported a positive association of morbidity or mortality with distance from the roadside. We conducted this study to assess the association of $PM_{2.5}$ concentrations measured at roadside hotspots with those at adjacent residential sites using real-time $PM_{2.5}$ monitors. We conducted real-time $PM_{2.5}$ measurements for rush hour periods (08:00~10:00 and 18:00~20:00) at 9 roadside air monitoring Hotspot sites in metropolitan Seoul over 3 weeks from October 1 to 21, 2013. Simultaneous measurements were conducted in residential sites within a 100 m radius from each roadside air monitoring site. A SidePak AM510 was used for the real-time $PM_{2.5}$ measurements. Medians of roadside $PM_{2.5}$ concentrations ranged from $9.8{\mu}g/m^3$ to $38.3{\mu}g/m^3$, while corresponding median values at adjacent residential sites ranged from $4.4{\mu}g/m^3$ to $37.3{\mu}g/m^3$. $PM_{2.5}$ concentrations of residential sites were 0.97 times of hotspot roadside sites. Distributions of $PM_{2.5}$ concentrations in roadside and residential areas were also very similar. Real-time $PM_{2.5}$ concentrations at residential sites, (100 m adjacent), showed similar levels to those at roadside sites. Increasing the distance between roadside and residential sites, if needed, should be considered to protect urban resident populations from $PM_{2.5}$ emitted by traffic related sources.

• Korean Journal of Veterinary Research
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• v.38 no.3
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• pp.544-552
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• 1998

A random study of 574 dairy farms in Gyeongnam area was designed to determine 1) management factors that may be associated with the occurrence of drug residues; 2) the dairy farmer's attitudes and knowledge about residues; 3) how these variables influence the occurrence of residues in dairy cattle. Management factors perceived as having the greatest influence on drug residues in milk were insufficient knowledge about withdrawal periods, errors due to hired help, insufficient identification and record of animals treated for mastitis, dry cow treatment for mastitis, and metritis treatment. Seventy-one percent of farms with residues problem used mixed own feeds compared with twenty-nine percent of farms with premedicated feeds. Factors significantly associated with the occurrence of residues were herd size, increased number of hired persons, increased frequency of use of mixed-own feeds, category of medicated feed, and producer's attitude toward the public health significance of residues. Our findings suggest that residue occurrence was mainly associated with errors due to hired help, insufficient knowledge about withdrawal periods, poor animal identification and records of treatment animals and use of medicated feeds. Any residue avodiance educational program needs to stress how to deal with these factors. This educational program should be directed to dairy farmers and employees, especially temporary employees. In addition, Dairy farmer's attitudes and knowledge about drug residues need to be improved. More evidence on the public healths significance of residues should be available to them. Because belife in importance of public healths concerns was related to successful residue avidance and because 81.3% of the dairy farmers with residue problem thought public healths concerns were less important than economic ones, it would be helpful to provide educational programs specifically directed to this issue. it may be useful to provide programs not only for the dairy farmers but also change of their concerns about on the public healths.

• Tuberculosis and Respiratory Diseases
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• v.49 no.4
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• pp.412-420
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• 2000

Background : There is increasing concern in many countries about the problem of drug-resistant tuberculosis. Prevalence of primary drug-resistant tuberculosis is the optimal epidemiological indicator for long term monitoring of national tuberculosis control program. Our purpose was The purpose of our study is to assess clinical characteristics and socioeconomic status of patients with drug-resistant tuberculosis. Method : We studied 68 cases with drug-resistant Mycobacterium tuberculosis infection diagnosed at the Ewha Womans University Mokdong Hospital from March, 1995 to February, 2000. Results : Patients with primary drug-resistant tuberculosis(PDR) were younger (39.6$\pm$16.3 years vs. 48.2$\pm$16.5 years ; p<0.05), had more population of less than more were under the age of 40 years aged -group(62.9% vs. 36.4% ; p<0.05) and were more highly educated than those with acquired drug-resistant tuberculosis(ADR)(38.9% vs. 11.1% ; p<0.05). In patients with ADR, the rates of familial history of tuberculosis and living in a rented house residence in a rented house were increased higher than compared with to those of patients with PDR. Patients with ADR had more involved lobes(2.0$\pm$0.8 vs. 1.4$\pm$0.7 ; p<0.01) and longer treatment duration than those with PDR(18.3$\pm$7.2 months vs. 10.6$\pm$6.3 months ; p<0.05). Patients with ADR showed larger numbers of resistant were resistant to more number of drugs, lower hospitalization rate and higher rate of self-interruption of medication than those with PDR. In patients with PDR, mono-drug resistance was increased, whereas poly- and multi-drug resistances were decreased compared with those with ADR. Resistance to isoniazid was the highest among antituberculosis drugs, and resistance to isoniazid in patients with ADR was higher than that in patients with PDR(90.9% vs. 71.4% ; p<0.05). Conclusions : Patients with ADR were more likely to include more population be of lower socioeconomic class, and patients with PDR seem seemed to be young and socially active population. For control of drug-resistant Mycobacterium tuberculosis infection, proper isolation and prevention of patient with drug-resistant tuberculosis are needed.

• Korean Journal of Community Nutrition
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• v.1 no.2
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• pp.161-177
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• 1996

This study attempts to propose a priority of national nutrition targets and strategies for health promotion by the year 2000 in Korea, as a part of the task set for national health promotion objectives and strategies. Among all of the important health issues raised, ten were chosen, nutrition was one priority area. In the first part, the current status of the nutrition-related health problems and risk factors are reviewed, in conjunction with the newly arisen health phenomena, such as changes in prevalence of lifestyle disease and causes of death, changes of food consumption patterns in our country. In the second section this study suggests six feasible national nutrition targets, eight implementing strategies and current major tasks on the basis of the assessment of present status and in consideration of the other health promotion goals and strategies, with reference to that of other developed countries. The main targets and strategies are suggested as follows ; Firstly, the national nutrition monitoring and surveillance system should be established for identifying the nutritional problems for our people, and current National Nutrition Survey is a strong need for improvement to a more comprehensive and reliable one. Secondly, effective administrative mechanism should be operation at national level for the development of nutrition policy. Ministry of Health and Welfare (MOHW) as well as local health department must be remarkably renewed and strengthened the nutrition section. And it is recommended that MOHW organize and operate “The Council of Nutrition”, in which all government authorities related with foodstuffs and nutrition would incorporated. The Council of Nutrition would act as an adjustor as well as a coordinator in nutrition related policy-making. Thirdly, healthy eating pattern will be supported by activities of introducing a nutrition labeling for providing consumers with the necessary information and skills for food selection. Fourthly, nutrition education, and nutrition intervention programs will be carried out in various settings such as health centers, schools, and clinical fields and workplace. Fifthly, the current dietary guidelines shall be continuously improved in detail, and publicly circulated to particular levels of people by age group and by health condition. And finally, researches and epidemiological studies particularly in regard to diet for development of chronic diseases are needed for more investigation and up-to-date national health and nutrition data should be collected with the support and cooperation from the various medical professional teams . (Korean J Community Nutrition 1(2) : 161-177, 1996)

• Journal of the Korean association of regional geographers
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• v.18 no.4
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• pp.473-493
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• 2012

Malaria infection is sensitively influenced by regional meteorological conditions along with global climate change. Remote sensing techniques have become an important tool for extraction of climatic and environmental factors, including rainfall, temperature, surface water, soil moisture, and land use, which are directly linked to the habitat qualities of malaria mosquitoes. Improvement of sensor fidelity with higher spatial and spectral resolution, new multinational sensor development, and decreased data cost have nurtured diverse remote sensing applications in malaria research. In 1984, eradication of endemic malaria was declared in Korea, but reemergence of malaria was reported in mid-1990s. Considering constant changes in malaria cases since 2000, the epidemiological management of the disease needs careful monitoring. Geographically, northmost counties neighboring North Korea have been ranked high in the number of malaria cases. High infection rates in these areas drew special attention and led to a hypothesis that malaria dispersion in these border counties might be caused by north-origin, malaria-bearing adult mosquitoes. Habitat conditions of malaria mosquitoes are important parameters for prediction of the vector abundance. However, it should be realized that malaria infection and transmission is a complex mechanism, where non-environmental factors, including human behavior, demographic structure, landscape structure, and spatial relationships between human residence and the vector habitats, are also significant considerations in the framework of medical geography.

• Asian Journal of Atmospheric Environment
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• v.9 no.4
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• pp.247-258
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• 2015

Exposure of high concentration of ground-level ozone (GLO) can trigger a variety of health problems including chest pain, coughing, throat irritation, asthma, bronchitis and congestion. There are substantial human and animal toxicological data that support health effects associated with exposure to ozone and associations have been observed with a wide range of outcomes in epidemiological studies. The aim of the present study is to estimate the spatial distributions of GLO using geostatistical method (ordinary kriging) for assessing the exposure level of ozone in the eastern part of Texas, U.S.A. GLO data were obtained from 63 U.S. EPA's monitoring stations distributed in the region of study during the period January, 2012 to December, 2012. The descriptive statistics indicate that the spatial monthly mean of daily maximum 8 hour ozone concentrations ranged from 30.33 ppb (in January) to 48.05 (in June). The monthly mean of daily maximum 8 hour ozone concentrations was relatively low during the winter months (December, January, and February) and the higher values observed during the summer months (April, May, and June). The higher level of spatial variations observed in the months of July (Standard Deviation: 10.33) and August (Standard Deviation: 10.02). This indicates the existence of regional variations in climatic conditions in the study area. The range of the semivariogram models varied from 0.372 (in November) to 15.59 (in April). The value of the range represents the spatial patterns of ozone concentrations. Kriging maps revealed that the spatial patterns of ozone concentration were not uniform in each month. This may be due to uneven fluctuation in the local climatic conditions from one region to another. Thus, the formation and dispersion processes of ozone also change unevenly from one region to another. The ozone maps clearly indicate that the concentration values found maximum in the north-east region of the study area in most of the months. Part of the coastal area also showed maximum concentrations during the months of October, November, December, and January.

• Journal of Life Science
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• v.22 no.5
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• pp.600-604
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• 2012

Rotavirus is the main cause of severe diarrhea in infants and young children of the world. However, the frequency of genetic alterations makes it hard to control the prophylaxis. Therefore, continuous monitoring of the rotavirus's genetic change is inevitable to prevent disease prevalence and is useful in inventing an efficient vaccine. From January 2005 to December 2010, we investigated 11,607 stool samples of acute gastroenteritis patients in the Incheon metropolitan area. About 13.18% (1,530 stool samples) of all samples had a positive reaction against rotavirus using an antigen capture enzyme-linked immunosorbent assay (ELISA). Then, the 160 stool samples were searched for subtypes of group A rotavirus by using a reverse transcription polymerase chain reaction (RT-PCR) and a nested multiplex RCR. In P sub-typing, P8 (56.3%) was an extremely prevalent genotype, followed by P6 (21.3%), and P1A (10.0%). G1 (39.4%) was most widespread in the G subtype, followed by G4 (25.0%) and G3 (18.8%). G1P8 (35.5%) was the most common G and P subtype combination, followed by G4P6 (19.3%) and G3P8 (13.1%). These results might be useful data for understanding the epidemiological status of group A-rotavirus dispersion in the Incheon metropolitan area.

• Journal of Microbiology and Biotechnology
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• v.14 no.1
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• pp.110-115
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• 2004

This study was undertaken to develop PCR primers for the simultaneous detection of Fusobacterium nucleatum and Actinobacillus actinomycetemcomitans, using two species-specific reverse primers in combination with a single conserved forward primer. These primers target the variable and conserved regions of the 16S rDNA. The primer specificity was tested against (i) four F. nucleatum and three A. actinomycetemcomitans strains and (ii) seven representatives of the different species of oral bacteria. The primer sensitivity was determined by testing serial dilutions of the purified genomic DNA of F. nucleatum and A. actinomycetemcomitans. The data indicate that species-specific amplicons could be obtained for all the F. nucleatum and A. actinomycetemcomitans strains tested, which were not found in the seven other species. The multiplex PCR could detect as little as 4 fg of chromosomal DNA of F. nucleatum and A. actinomycetemcomitans simultaneously. These findings suggest that these PCR primers are highly sensitive and are suitable for applications in epidemiological studies, diagnosis, and monitoring F. nucleatum and A. actinomycetemcomitans after the treatment of periodontitis.