• 보건교육건강증진학회지
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• 제18권2호
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• pp.129-140
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• 2001

Harmful environment around school area have been increased with socio-economic development in Korea. Those entertainment facilities have caused a negative effect on the learning environment in many schools. As a result of increased entertainment harmful facilities in school area, the numbers of deviant behaviors such as drinking, smoking, substance abuse and sexual activity among junior high school students have been significantly increased. Given this situation, the aim of this study was to describe the distribution of the facilities; to access applied(experience) of the facilities according to students demographic variables; and to identify the relationship between use of the facilities and students risk health behaviors such as smoking, drinking, substance abuse and sexual activity. The field theory was used to study the relationship between the use of the facilities and risk health behaviors among students. A self-administered questionnaire survey was conducted in Korea. 2,114 junior and senior high school students(middle and high school students) were recruited by the method of proportional stratified random sampling from June to July 2000. Results indicated that: 1) The rates of using game centers, PC rooms, Song rooms and comic rooms were 78.3%, 75.6%, 71.6%, and 34.3% respectively. 2) High school students visited the entertainment facilities significantly more than middle school students(p〈0.001). 3) The rates of using facilities near schools were significantly associated with parents job(p〈0.05). 4) The rates of drinking, smoking, drug abuse, and sexual activity were 21.6%, 11.9%, 4.3% and 1.6% respectively. 5) Risk health behaviors such as smoking(p〈0.001) and drinking(p〈0.001), amount of smoking and drinking(p〈0.001) and sexual activity(p〈0.05) were associated with the experience of using the facilities. Those who had drinking experience were more likely to go the facilities than those without drinking experience. Also, those who were smoker had higher probability of going using the facilities than non-smokers.

• 한국컴퓨터정보학회논문지
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• 제28권8호
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• pp.165-174
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• 2023

본 연구는 국내 근로환경조사 자료를 이용하여 조사 시기에 따른 제조업 종사자의 유해·위험요인 노출과 결근과의 관련성을 확인하였다. 이에 2011년도(3차), 2017년도(5차), 2020년도(6차)의 유해·위험요인 동일문항에 대하여 제조업 종사자 8,318명을 대상으로 분석하였다. 업무 관련 유해·위험인자와 결근과의 관련성을 보면 2011년도에 비하여 2020년도에 진동, 소음, 높은 온도, 먼지 등의 흡입, 증기흡입, 화학물질 취급, 감염물질 취급에서 노출 시간 3/4 이상이 결근에 영향을 미치는 것으로 나타났다. 결론적으로 업무 관련 유해·위험요인에 대해서는 조사시기가 증가함에 따라 비노출이 증가함을 알 수 있었고 업무 관련 유해·위험요인의 노출 시간이 결근에 영향을 미친다는 것을 확인할 수 있었다.

• 산업경영시스템학회지
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• 제30권4호
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• pp.71-77
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• 2007

In this study, reactions of central nervous systems working against different conditions of forced frequency and acceleration were measured and analyzed. The experiment are conducted with health men. The steady vibration conditions of forced frequency (0.315m/s2-1.0Hz, 0.315m/s2-10Hz and 10Hz-1.0m/s2) are used and the waves of EEG (Electroencephalogram) are measured. As a result, this paper shows that the ${\alpha}-wave$ of frontal lobe transfers from low to high frequency band under the vibration environment. Additionally, the average frequency of ${\alpha}-wave$ is higher under the vibration than under non-vibration environment. In the case of forced frequency of 1.0Hz-0.315m/s2, the feeling with the vibration are nearly same compared with the non-vibration condition. But in the case of 10Hz-1.0m/s2, uncomfortable feeling increased compared with the non-vibration condition. This study also shows the relationship between fluctuation slop and feeling. From this study, it is found that the effect of vibration on human depends on acceleration characteristics. Highly accelerating vibration is more harmful to human.

• Applied Microscopy
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• 제34권2호
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• pp.103-111
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• 2004

수생식물 개구리밥(Spirodela polyrhiza)의 식물체 발달 과정에서 나타나는 미생물과의 상호관계를 주사전자현미경 및 세포학적으로 추적하여 연구하였다. 개구리밥은 부유성 식물로 분화 발달 초기부터 잠수부위에 여러 종류의 박테리아, 남조류, 규조류 등이 서식하였다. 미분화된 어린 식물체에는 성숙 발달한 식물체에 비해 미생물들이 낮은 빈도로 출현하였고, 성숙한 식물체에서는 특히 엽상체 하피에 가장 많은 미생물들이 서식하였으며, 그 다음으로는 점액성 물질이 층을 이루는 근관에 많이 관찰되었다. 반면, 신장 발달 중의 뿌리에는 일반적인 분포를 보였으며, 상피에는 미생물이 거의 분포하지 않는 양상을 보였다. 이들 미생물이 개구리밥 조직 내에 침입하여 식물체에 어떠한 영향을 미치는가를 조사하기 위해 엽상체, 연결사, 뿌리, 근관, 무성생식낭 등의 구조를 세포학적으로 추적한 결과, 어느 부위에서도 조직 내로 미생물이 침입하여 세포를 괴사시키거나 감염시키는 일은 거의 관찰되지 않았다. 그러므로, 개구리밥 식물체의 발달과정에 있어 미생물들은 어떠한 해를 주지 않는 것으로 추정된다. 이후 개구리밥에 서식하는 미생물의 질소고정치를 측정하여 그 기능을 식물체의 세포학적 측면과 접목시켜 연구하면 개구리밥과 미생물과의 상호관계가 공생적인지를 더 확실하게 밝힐 수 있을 것이다.

• Ocean and Polar Research
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• 제28권1호
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• pp.57-65
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• 2006

Various marine plankton were observed in the ballast water of vessels entering Incheon and Busan harbors. The ballast water of which age ranged from 2 to 54 days originated from the coastal waters of New Zealand, Taiwan, Singapore, Japan, Hong Kong and Pakistan, and from the Pacific Ocean. The total number of marine plankton taxa in 9 ballast tanks of different ships was 170: 90 phytoplankton, 24 protozoa and 56 zooplankton. The most diverse taxonomic groups were diatoms in phytoplankton, ciliates in protozoa and copepods in zooplankton. Classifying the specimens by size, above 50% of the number species of phytoplankton belonged to the size range between 50 and 150 Un. Protozoa and metazooplankton were found frequently in the size range between 50 and $120{\mu}m$ and 500 and $1,000{\mu}m$, respectively. The relationship between the species number and the age of ballast water was not significant. This is because of difference of filtration amounts derived from discordance of collecting samples. Among plankton observed in ballast water, some harmful algae and non-indigenous aquatic species were identified. Therefore, we need to investigate whether these species can inhabit in Korean coastal waters in further study.

• 한국미생물·생명공학회지
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• 제34권1호
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• pp.1-6
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• 2006

Harmful algal blooms (HABs or red tides), caused by uncontrolled proliferation of marine phytoplankton, impose a severe environmental problem and occasionally threaten even public health. We sequenced the genome of an EPS-producing marine bacterium Hahella chejuensis that produces a red pigment with the lytic activity against red-tide dinoflagellates at parts per billion level. H. chejuensis is the first sequenced species among algicidal bacteria as well as in the order Oceanospirillales. Sequence analysis indicated a distant relationship to the Pseudomonas group. Its 7.2-megabase genome encodes basic metabolic functions and a large number of proteins involved in regulation or transport. One of the prominent features of the H. chejuensis genome is a multitude of genes of functional equivalence or of possible foreign origin. A significant proportion (${\sim}23%$) of the genome appears to be of foreign origin, i.e. genomic islands, which encode genes for biosynthesis of exopolysaccharides, toxins, polyketides or non-ribosomal peptides, iron utilization, motility, type III protein secretion and pigment production. Molecular structure of the algicidal pigment was determined to be prodigiosin by LC-ESI-MS/MS and NMR analyses. The genomics-based research on H. chejuensis opens a new possibility for controlling algal blooms by exploiting biotic interactions in the natural environment and provides a model in marine bioprospecting through genome research.

• Annals of Pediatric Endocrinology and Metabolism
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• 제23권4호
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• pp.182-195
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• 2018

Increasing prevalence of childhood obesity poses threats to the global health burden. Because this rising prevalence cannot be fully explained by traditional risk factors such as unhealthy diet and physical inactivity, early-life exposure to endocrine disrupting chemicals (EDCs) is recognized as emerging novel risk factors for childhood obesity. EDCs can disrupt the hormone-mediated metabolic pathways, affect children's growth and mediate the development of childhood obesity. Many organic pollutants are recently classified to be EDCs. In this review, we summarized the epidemiological and laboratory evidence related to EDCs and childhood obesity, and discussed the possible mechanisms underpinning childhood obesity and early-life exposure to non-persistent organic pollutants (phthalates, bisphenol A, triclosan) and persistent organic pollutants (dichlorodip henyltrichloroethane, polychlorinated biphenyls, polybrominated diphenyl ethers, per- and polyfluoroalkyl substances). Understanding the relationship between EDCs and childhood obesity helps to raise public awareness and formulate public health policy to protect the youth from exposure to the harmful effects of EDCs.

• Toxicological Research
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• 제33권1호
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• pp.31-41
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• 2017

Side stream cigarette smoke (SSCS) is known to be as harmful and hazardous to human health as is active smoking. In this study, we investigated the relationship between the exposure to SSCS and its stimulatory and subacute effects on the progression of non-alcoholic steatohepatitis (NASH). A methionine and choline-deficient plus high fat (MCDHF) diet was administered to C57BL/6 mice for 6 weeks. During the first three weeks of MCDHF diet feeding, each diet group was exposed to SSCS (0, 20, $40{\mu}g/L$) or fresh air for 2 hrs per day and 5 days per week. Additional experiments were performed by increasing the concentration (0, 30, $60{\mu}g/L$) and exposure time (6 hours per day) of SSCS. According to histopathologic analysis and serum levels of Alanine Aminotransferase (ALT) and Aspartate Aminotransferase (AST), there were no differences in hepatic fat deposition, fibrosis, apoptosis or liver damage in MCDHF-fed mice based on SSCS exposure. There were also no differences in the expression of inflammation-, oxidative stress- or fibrosis-related genes between MCDHF-fed mice with or without SSCS exposure. Therefore, it is concluded that SSCS with current exposure amounts does not have additive detrimental effects on the early stage of NASH.

• 품질경영학회지
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• 제43권3호
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• pp.359-372
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• 2015

Purpose: Through studying the expert's and non-experts panel responses to the questions regarding the attributes of chemical-biological protection cloth quality in terms of the levels of customer demand and technical factors has been studied. We are applied to a QFD matrix with find out the relationship between the selective removal efficiency of chemical-biological cloth and the guidelines of technical approach. Methods: We fabricated several composite of ion-exchange resins with selectively permeable performance designed to facilities water vapor transport and selective adsorption of the harmful gases. With these materials, we characterized on the selectively permeable performance to identify ion-exchange resin with chemical-biological protective cloth. Results: Results showed that ion exchange materials possessed performance with selectively efficiencies as NH3, SOx, NOx and HCl gas. The selective adsorption amount of ammonia and hydrogen gases were $90-80{\mu}g/g$ with TRILITE SCR-BH sulfonated ion exchange resin. The PP non-woven/ion exchange resin adsorbent materials possessed performance with water vapor permeability were 1,100-1,350 g/m2/day, it's was two times high value compare with activated carbon. With these materials, we characterized selectively removal efficiency to identify new ion-exchange material with chemical-biological protective capability. Conclusion: This study shows that a QFD aids in deciding with of the adsorption parameters to optimized with chemical-biological protection cloth manufacturing.

• 한국환경보건학회지
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• 제50권2호
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• pp.146-156
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• 2024

Background: Children who use playground facilities are exposed to potential risks due to the high concentration of heavy metals contained in the finishing materials of facilities in children's playgrounds. Objectives: The purpose of this study was to investigate the concentration of heavy metals in the finishing materials of outdoor children's playgrounds where harmful heavy metals exist in Gwangju and to conduct human risk assessment for children and adults by age to find the risks and limitations. Methods: The bottom and top layers of double-painted paint were peeled off and collected together from the finishing materials of children's play facilities such as slides, swings, and seesaws in 147 children's parks in Gwangju. Heavy metals were analyzed using ICP-OES, etc., and human risk assessment was performed using the concentrations of heavy metals. Results: Based on 1.0E-04, which requires legal regulation, CTE was found to pose a carcinogenic risk for preschool children and no carcinogenic risk for the rest of the age groups. However, RME showed that both men and women of all ages had a carcinogenic risk. For reference, when the carcinogenic risk was based on 1.0E-06, CTE was found to pose a carcinogenic risk from infants to elementary school students, and RME was found to have a carcinogenic risk in all age groups. It was judged that there is a non-carcinogenic risk if the non-carcinogenic risk exceeds 1 based on the hazard index (HI) 1. In CTE, there was no non-carcinogenic risk, and RME for preschooler males (1.49E+00) and females (1.56E+00) were found to have non-carcinogenic risk. Conclusions: This study was meaningful in that it examines the differences in the current management of heavy metals concentration standards and potential carcinogenic and non-carcinogenic risks to the human body and discusses the relationship between heavy metals and human health effects.