• Journal of radiological science and technology
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• v.35 no.2
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• pp.141-149
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• 2012

The aims of this study are to assess external radiation exposed doses of body and hands of nuclear medicine workers who handle radiation sources, and to measure radiation exposed doses of the hands induced by a whole body bone scan with high frequency and handling a radioactive sources like $^{99m}Tc$-HDP and $^{18}F$-FDG in the PET/CT examination. Skillful workers, who directly dispense and inject from radiation sources, were asked to wear a TLD on the chest and ring finger. Then, radiation exposed dose and duration exposed from daily radiation sources for each section were measured by using a pocket dosimeter for the accumulated external doses and the absorbed dose to the hands. In the survey of four medical institutions in Incheon Metropolitan City, only one of four institutions has a radiation dosimeter for local area like hands. Most of institutions uses radiation shielding devices for the purpose of protecting the body trunk, not local area. Even some institutions were revealed not to use such a shielding device. The exposed doses on the hands of nuclear medicine workers who directly handles radioactive sources were approximately twice as much as those on the body. The radiation exposure level for each section of the whole body bone scan with high frequency and that of the PET/CT examination showed that radiation doses were revealed in decreasing order of synthesis of radioactive medicine and installation to a dispensing container, dispensing, administering and transferring. Furthermore, there were statistically significant differences of radiation exposure doses of the hands before and after wearing a syringe shielder in administration of a radioactive sources. In this study, although it did not reach the permissible effective dose for nuclear medicine, the occupational workers were exposed by relatively higher dose level than the non-occupational workers. Therefore, the workers, who closely exposed to radioactive sources should be in compliance with safety management regulations, and take actions to maximally reduce locally exposed dose to hands monitoring with ring TLD.

• Journal of Preventive Medicine and Public Health
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• v.30 no.3 s.58
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• pp.567-576
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• 1997

To evaluate the effects of reflected glare on eyes, authors assessed the periodic health examination(1991-1996) & self-administered questionnaire data of a semiconductor producing company. The 13 lead frame(LF) department workers have been exposed to high reflected glare in the process for examining the silver plating products. We compared the data of connector(14) and clerical(12) workers as the non-exposed ones. Among LF department workers, 100% felt their visual acuity worsened(connector:81.8%, clerical:85.7%), and 70% had worn the glasses o. contact lenses(connector : 14.3%, clerical :40%) since working at the company. Major ophthalmic symptoms of the LF workers are asthenopia, tearing, decreased visual acuity, congestion and glare. Decrease of visual acuity by Hahn's line change of the LF workers is significantly high during a 5-year follow-up(p<0.05 by simple regression) compared with connector clerical workers.

• The Journal of Korean Academy of Sensory Integration
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• v.19 no.1
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• pp.69-82
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• 2021

Objective : This recent work intended to provide basic information for researchers and practitioners related to occupational therapy about Developmental Coordination Disorder (DCD) in South Korea. The previous research of screening DCD and the effects of intervention programs were reviewed. Methods : Peer-reviewed papers relating to DCD and published in Korea from January 1990 to December 2020 were systematically reviewed. The search terms "developmental coordination disorder," "development coordination," and "developmental coordination" were used to identify previous Korean research in this area from three representation database, the Research Information Sharing Service, Korean Studies Information Service System, and Google Scholar. We found a total of 4,878 articles identified through the three search engines and selected seventeen articles for analysis after removing those that corresponded to the overlapping or exclusion criteria. We adopted "the conceptual model" to analyze the selected articles about DCD assessment and intervention. Results : We found that twelve of the 17 studies showed the qualitative level of Level 2 using non-randomized approach between the two groups. The Movement Assessment Battery for Children and its second edition were the most frequently used tools in assessing children for DCD. Among the intervention studies, the eight articles (47%) were adopted a dynamic systems approach; a normative functional skill framework and cognitive neuroscience were each used in 18% of the pieces; and 11% of the articles were applied neurodevelopmental theory. Only one article was used a combination approach of normative functional skill and general abilities. These papers were mainly focused on the movement characteristics of children with DCD and the intervention effect of exercise or sports programs. Conclusion : Most of the reviewed studies investigated the movement characteristics of DCD or explore the effectiveness of particular intervention programs. In the future, it would be useful to investigate the feasibility of different assessment tools and to establish the effectiveness of various interventions used in rehabilitation for better motor performance in children with DCD.

• The Journal of Korean Academy of Sensory Integration
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• v.21 no.2
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• pp.69-83
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• 2023

Objective : This study sought to systematically examine the intervention effect of social stories when applied in relation to children with sleep disorders. Methods : Studies available in the SCOPUS, ScienceDirect, PsycArticles, and PubMed databases that were published from 2001 to 2022 were searched. The keywords used for the search were as follows: ("social story" OR "social stories") AND ("sleep" OR "sleep disorders" OR "sleep wake disorder bedtimes" OR "sleep initiation and maintenance disorders" OR "sleep wake disorder" OR "sleep arousal disorders"). Based on the selection criteria, six experimental studies were selected and analyzed. Results : The selected studies were two randomized controlled trials, three individual trials, and one case study. The subjects were mostly children diagnosed with autism spectrum disorder who were school-aged or adolescent. The intervention types were often complex interventions, including social stories and other interventions, while the durations of the interventions varied from one day to more than 40 days. The interventions had a positive effect on the subjects' sleep quality, with night wakings, sleep onset delay, and sleep anxiety all being improved. As standardized assessment tools to evaluate the effectiveness of social stories, the Child Sleep Habits Questionnaire and the Child Behavior Checklist were used in two papers each, and were the most commonly used. As non-standardized assessment tools, each of the four papers used turbulence and sleep diaries as assessment tools. Conclusion : The effect of social story mediation can be divided into sleep quality and sleep-related behavior. In terms of sleep quality, studies showing improvements in night wakings, sleep onset delay, and sleep anxiety accounted for a large proportion of the sample. The detailed effect area of sleep quality showed a significant improvement after the interventions in most studies, and in all six studies analyzed in the present study, the continuation of the effect after the intervention was confirmed via follow-up tests. Thus, the findings of this study are expected to be helpful when applying social stories in children with sleep disorders in clinical practice due to presenting the intervention effects, outcome evaluation tools, and intervention periods in children with sleep disorders in prior investigations involving social stories.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.10 no.1
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• pp.1-17
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• 2000

Carcinogen-DNA adduct analysis has potential for biomonitoring the earliest effects of exposure to many chemical carcinogens. They are the covalent reaction products of electrophiles and nucleophilic sites on DNA and the initial damage to DNA induced by many carcinogens. So many researchers begin to use them as biomarker for monitoring the earliest exposure of carcinogens and develop the effective analytical techniques about them. Randerath, Gupta and coworkers(1981, 1982) has also developed a $^{32}P$-postlabelling method as one among them. A major project for biomonitoring workers with carcinogen-DNA adducts is to develop non-invasive samples instead of tissues of target organs such as baldder and lung. This study use the exfoliated urothelial cells in urine for examine benzidine-DNA adducts. The content of exfoliated urothelial cells is not enough to significantly measure DNA content with spectrophotometer, and require the another way. So firstly washing the collected cells with PBS and 70% ethanol and centrifuge them for removing the crystals in urine, which block the isolation of DNA adducts. And then, measure the total nucleotide after $^{32}P$-postlabelling for calculating RAL. $[{\gamma}-^{32}P]ATP$ using for $^{32}P$-postlabelling, can synthesize with $[^{32}P]H_3PO_4$, and reagent and enzyme mixture (RM, EM), which is very economic in case of requiring a lot of them. Chromatography was composed of two steps. First step was to separate adduct ones from unadducted nucleotide, and secondary step was separate each adduct, which were performed with 4 kinds of solvents and different directions on TLC. With this procedure, we measure the DNA adducts in exfoliated urothelial cells of workers who were employed in benzidine and benzidine-dye company. RAL of adducts were $89.0{\times}10^7$ and $57.0{\times}10^7$ in them. In conclusion, we can significantly measure the DNA adduct in exfoliated urothelial cells by using the above $^{32}P$-postlabelling procedures, and use them to be biomonitoring workers who exposed carcinogens.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.24 no.4
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• pp.453-461
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• 2014

Objective: Based on the fact that fine particles are more likely to produce negative influences on the health of occupants as well as the quality of indoor air compared to coarse particles, it is critical to determine concentrations of aerosol particles with different sizes. Thus, this study focused on the size distribution and concentrations of aerosol particles in university buildings. Method: Aerosol particles in indoor air were collected from four areas: corridors in buildings(In-CO), lecture rooms(In-RO), laboratories(In-LR), and a cafeteria(In-RE). Samples were also collected from outside for comparison between the concentrations of indoor and outdoor particles. For the collection of the samples, an eight stage non-viable cascade impactor was used. Result: The average concentration of $PM_{10}$ in the samples collected from indoor areas was $34.65-91.08{\mu}g/m^3$,and the average for $PM_{2.5}$ was $22.65-60.40{\mu}g/m^3$. The concentrations of the aerosol particles in the corridors, lecture rooms, and laboratories were relatively higher than the concentrations collected from other areas. Furthermore, in terms of mass median aerodynamic diameter(MMAD), the corridors and lecture rooms had higher numbers due to their characteristics, showing $2.36{\mu}m$ and $2.11{\mu}m$, respectively. Laboratories running an electrolysis experiment showed $1.58{\mu}m$, and the cafeteria with regular maintenance and ventilation had $1.96{\mu}m$. Conclusion: The results showed that the $PM_{10}$ concentrations of all samples did not exceed indoor air quality standards. However, the $PM_{2.5}$ concentration was over the standard and, in particular, the concentration of fine particles collected from the laboratories was relatively higher, which could be an issue for the occupants. Therefore, it is important to improve the quality of the indoor air in university buildings.

• Journal of Preventive Medicine and Public Health
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• v.36 no.4
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• pp.303-313
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• 2003

General information is summarized, that is necessary to introduce a scientific assessment of the human health and exposure issue concerning dioxin and dioxin-like compound. Scientific literatures were reviewed to assess the background exposures to the dioxin-like compounds for normal residents. Epidemiologic studies were also reviewed to assess malignant and nonmalignant sweets of dioxins. In 1997, the International Agency for Research on Cancer classified 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) as a human carcinogen, primarily based on occupational cohort studies. The US Environmental Protection Agency made the same decision in it's Draft Dioxin Reassessment. Epidemiologic evidences point to a generalized excess of all cancers, without any pronounced excess at specific sites. Reported non-cancer effects included a range of conditions affecting most systems. Among them, chloracne, elevation in gamma glutamyl transferase(GGT), and alterations in reproductive hormones are related to TCDO, Other adverse outcomes, such as lipid concentrations, diabetes, circulatory and heart diseases, immunologic disorders, neurobehavioral effects, and developmental outcomes require further study before their respective relationships to TCDD can be more definitively assessed.

• Journal of the Korean Geographical Society
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• v.32 no.4
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• pp.491-510
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• 1997

The main purpose of this study is to analyse and explain the occupational pattems of Korean immigrants in Auckland, New Zealand, in order to understand how they are adapting to New Zealand society. We analysed the Korean telephone directory from 1992 to 1996 and listings of Korean businesses in the biweekly magazine 'Korea Town'. The bulk of Korean immigration started in 1991 when the New Zealand govemment opened up its immigration doors to non-Europeans. Clearly, recent Korean immigration has experienced exponential growth. The range of Korean's occupations has grown gradually compared to the growth of Korean immigration, from about 20 different kinds of occupations in 1992 to 55 in 1997. In 1992, there were only 37 korean businesses listed, but in 1997, there are about 636-a growth of over 1,600${\%}$. As we analysed all Korean businesses, we found that almost all Korean businesses and occupations have not penetrated the host society economy but reflect typical characteristics of ethnic businesses, in tems of capital, business operation, employees and customers being mainly Korean, Korean businesses are concentrated in the City Centre and North Shore. The concentration in North Shore reflects the concentration of Korean residents in this area, while Korean businesses in the City centre are mostly tourist industries(travel agencies, souvenir shops)and restaurants. The findings of this study closely reflect similar Westem studies on ethnic minority businesses. From this, we can conclude that Korean businesses at the moment reflect the initial stage of Korean communities in New Zealand.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.16 no.4
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• pp.324-333
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• 2006

This study was designed to investigate the effect of bone demineralization and tibia lead on blood lead in retired lead workers. Two hundred thirty five(126 females and 109 males) retired lead workers who worked in 4 different lead factories and 101 non-occupationally lead exposed subjects(51 females and 51 males) were recruited from March 2004 to October 2004. Bone mineral density(BMD) was measured at left calcaneous bone area by broadband ultrasound attenuation(BUA) method with QUS-2(Metra Biosystems Inc, USA). The BUA value transformed into T-score by WHO standard conversion criteria. Tibia bone lead was measured for skeletal bone lead with K-xray fluorescence(K-XRF) and blood lead was analyzed with flameless atomic spectrophotometer. Hemoglobin, hematocrit, serum calcium and iron were also analyzed. In addition, information for smoking and drinking status and basic personal data such as age, gender and lead exposure were also collected using questionnaire inquiry. Blood lead was correlated with tibia lead (r=0.664) and these two variables were negatively correlated with BMD in bivariate analysis. BMD showed significant main effect on the change of blood lead independent to tibia lead without any effect modification of age or gender; the one T-score unit decrease of mineral bone density made $0.43{\mu}g/dl$ increase of blood lead. On the other hand, tibia lead showed effect modification with gender on blood lead; the slope of tibia lead on blood lead in male was steeper than in female and crossed at around zero of tibia lead. In the multiple regression analysis of blood lead and tibia lead on BMD after adjustment of related covariates, only blood lead showed statistically significant effect on BMD. This study confirmed that BMD and blood lead were significantly associated. To verify the causal association of BMD on blood lead and vice versa, further longitudinal studies are needed.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.21 no.3
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• pp.139-145
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• 2011

Objectives: This investigation is purposed to evaluate the airborne asbestos concentrations in the public buildings having asbestos containing materials(ACMs) in Seoul. Methods: The Seoul Metropolitan Government carried out an asbestos survey to the city-owned public buildings to identify the level of risk exposure, classified into low, moderate and high risk. To evaluate the airborne concentration of asbestos, 11 sampling sites in ten buildings based on the survey were selected. The air samples from the eleven sites were analyzed by Phase Contrast Microscopy(PCM) and Transmission Electron Microscopy (TEM), and compared the analytical results from the both. Results: 1. The airborne fiber concentrations by PCM were less than the detection limit($7f/mm^2$) in 9(82%) out of 11 sampling sites. The highest concentration was 0.0043 f/cc, but it was below the guideline value for indoor air quality(0.01 f/cc), proposed by the Ministry of Environment, Korea. 2. In two sampling sites, having moderate risk level, the chrysotile was identified and showed it's concentrations of 0.0102 s/cc and 0.0058 s/cc, less than $5{\mu}m$ lengths. 3. The ACMs identified in the two sampling sites were a packing material(65% of chrysotile) in mechanical area and a thermal system insulation(5% of chrysotile) in a boiler room. Having more possibility of asbestos emission in the mechanical area, it would be required to set up and carry out the asbestos management plan. Conclusions: Based on the result of this study, the airborne asbestos concentrations in the public buildings with ACMs were generally lower than the guideline value for indoor air quality. There are widespread concerns about the possible health risk resulting from the presence of airborne asbestos fibers in the public buildings. Most of the previous studies about airborne asbestos analysis in Korea were performed based on PCM method that asbestos and non-asbestos fibers are counted together. In the public and commercial buildings, having ACMs, it is suggested that the asbestos be analyzed by TEM method to identify asbestos due to concerns about asbestos exposure to workers and unspecified people.