• Title/Summary/Keyword: Dong Hae

Search Result 2,813, Processing Time 0.029 seconds

Microbial Exposure Assessment in Sawmill, Livestock Feed Industry, and Metal Working Fluids Handling Industry

  • Park, Hyun-Hee;Park, Hae-Dong;Lee, In-Seop
    • Safety and Health at Work
    • /
    • v.1 no.2
    • /
    • pp.183-191
    • /
    • 2010
  • Objectives: The objective of this study is to investigate the distribution patterns and exposure concentrations of bioaerosols in industries suspected to have high levels of bioaerosol exposure. Methods: We selected 11 plants including 3 livestock feed plants (LF industry), 3 metal working fluids handling plants (MWFs industry), and 5 sawmills and measured total airborne bacteria, fungi, endotoxins, as well as dust. Airborne bacteria and fungi were measured with one stage impactor, six stage cascade impactor, and gelatin filters. Endotoxins were measured with polycarbonate filters. Results: The geometric means (GM) of the airborne concentrations of bacteria, fungi, and endotoxins were 1,864, $2,252\;CFU/m^3$, and $31.5\;EU/m^3$, respectively at the sawmills, followed by the LF industry (535, $585\;CFU/m^3$, and $22.0\;EU/m^3$) and MWFs industry (258, $331\;CFU/m^3$, and $8.7\;EU/m^3$). These concentrations by industry type were significantly statistically different (p < 0.01). The ratio of indoor to outdoor concentration was 6.2, 1.9, 3.2, and 3.2 for bacteria, fungi, endotoxins, and dust in the LF industry, 5.0, 0.9, 2.3, and 12.5 in the MWFs industry, and 3.7, 4.1, 3.3, and 9.7 in sawmills. The respiratory fractions of bioaerosols were differentiated by bioaerosol types and industry types: the respiratory fraction of bacteria in the LF industry, MWF industry, and sawmills was 59.4%, 72.0%, and 57.7%, respectively, and that of fungi was 77.3%, 89.5%, and 83.7% in the same order. Conclusion: We found that bioaerosol concentration was the highest in sawmills, followed by LF industry facilities and MWFs industry facilities. The indoor/outdoor ratio of microorganisms was larger than 1 and respiratory fraction of microorganisms was more than 50% of the total microorganism concentrations which might penetrate respiratory tract easily. All these findings suggest that bioaerosol in the surveyed industries should be controlled to prevent worker respiratory diseases.

Interference Fringe Signal Filtering Method for Performance Enhancing of White Light Interfrometry (가간섭 영역 외의 배경 잡음성 간섭무늬 신호 필터링을 통한 백색광 주사간섭계의 성능 향상)

  • Yim, Hae-Dong;Lee, Min-Woo;Lee, Seung-Gol;Park, Se-Geun;Lee, El-Hang;O, Beom-Hoan
    • Korean Journal of Optics and Photonics
    • /
    • v.20 no.5
    • /
    • pp.272-275
    • /
    • 2009
  • In order to enhance the background noise filtering performance of the white light interferometry(WLI), we demonstrate the noise filtering performance of preprocessing of the measured fringe signals. The WLI was realized through a mirau interferometer which was equipped with a green LED. When measuring large-height and rough surface objects, the illumination optics are considered the numerical aperture(NA) and the depth of focus(DOF). In this case, the limited NA of the illumination optics has a considerable impact on the interference fringe. Therefore, we propose a preprocessing method that uses the intensity difference between the measured intensity and the moving average intensity. The performance is demonstrated by measuring an array of metal solder balls fabricated on printed circuit board(PCB). The proposed method reduces the noise pixels by 15 percent.

Isolation and Antimicrobial Susceptibility of Campylobacter jejuni from Diarrhea Patients (설사환자에서 Campylobacter jejuni의 분리 및 항생제 감수성 특성)

  • Park, Eun-Hee;Kim, Joung-A;Choi, Seung-Hwa;Bin, Jae-Hun;Cheigh, Hong-Sik;Suk, Dong-Hee;Lee, Su-Chul;Kim, Young-Hui
    • Journal of Life Science
    • /
    • v.17 no.6 s.86
    • /
    • pp.811-815
    • /
    • 2007
  • ln this study we isolated 27 isolates of Campylobacter jejuni from stool samples of 882 diarrheal patients. The seasonal distribution of patients was highest at July (11.7%). All the isolates of C. jejuni hydrolyzing sodium hippurate were serotyped on basis of heat-stable antigens, and identified with the use of passive hemagglutination assay. A total of 59.3% among 27 C. jejuni isolates were identified into 6 different serotypes, which serotype HS2, HSl/44, and HS2l were dominant. Antibiotics resistant rates of C. jejuni isolates were shown to be 100%, 63.0%, 51.9%, 37.0%, 33.3%, 25.9% and 7.4% to cephalothin, trimethoprim- sulfamethoxazole, tetracycline, ciprofloxacin, ampicillin, gentamycin and clindamycin, respectively. All isolates were sensitive to the erythromycin and imipenem.

High Luminance $Zn_2$$SiO_4$:Mn Phosphors for in PDP Application (고상법에 의한 PDP용 고휘도 $Zn_2$$SiO_4$:Mn 형광체 제조)

  • Jeon, Il-Un;Son, Gi-Seon;Jeong, Yang-Seon;Kim, Chang-Hae;Park, Hui-Dong
    • Korean Journal of Materials Research
    • /
    • v.11 no.3
    • /
    • pp.227-235
    • /
    • 2001
  • In this work, Zn$_2$SiO$_4$:Mn phosphors were prepared by solid state reaction. The effect of sintering/reduction temperature, flow rate of H$_2$-5%/$N_2$-95% mix gas, and ball milling conditions have been investigated on the sake of PDP(Plasma Display Panel) application. The characteristics such as particle morphology and photoluminescence of prepared phosphors were compared to those of commercial Zn$_2$SiO$_4$:Mn Phosphors. It was found that the Phosphor synthesized at 130$0^{\circ}C$ with 0.08 Mn concentration had a maximum brightness, This brightness was increased more 20% by reduction treatment under 100me/min flow rate of 5%H$_2$-95%$N_2$ mixed gas. The size of particles decreased under 3$\mu\textrm{m}$ after ball milling. Especially, higher luminescence was obtained in our Zn$_2$SiO$_4$:Mn phosphors than commercial Zn$_2$SiO$_4$:Mn phosphors, so that they are able to be applied for PDP.

  • PDF

Study on the Obese Students' Stress and Coping Method in Middle and High Schools (비만 중.고등학생의 스트레스와 대처방법에 관한 연구)

  • Kim, Yi-Soon
    • Research in Community and Public Health Nursing
    • /
    • v.12 no.3
    • /
    • pp.732-745
    • /
    • 2001
  • This study attempted to identify obese students' stress and coping method in middle and high schools. The data were collected from the total of 600 obese students from middle and high schools in Pusan. The author used a convenience sampling method. The data collection was done from March 2 to April 30. 2001. The analysis of the data was done with SPSS Win(10.0) for descriptive statistics. t-test. and ANOVA. The instrument used for the obese students' stress and coping method was a questionnaire developed by Kim. Yi-Soon and Kim. Young-Hae(200l). The tool was composed of 65 items (33stress items: 32coping method items) with the five-point Likert scale. The results were as follow: 1. The average score of stress was 2.49 (SD = .86) points in the male students. and 2.83(SD= .86) points in the female students. The subcategories were: (outward appearance), (boyfriend/girlfriend), (occurrence of an outbreak of a disease), (relationship within the family), (an obese appearance), (difficulty in exercise). The highest degree of stress came from 'an obese appearance' for the male students (mean=2.64. SD=0.87) and (mean=2.64. SD=0.87) for the female students. 2. The subcategories of the coping method were: (be concerned about other matters), (recreation activities), (self-violence), (relaxation), (hobby activities), (avoid a situation), (communication), (music), (negative behavior), (positive thinking). The highest degree of coping method were (recreation activities) in the male students (mean=3.07. SD=0.86) and (music) in the female students (mean=3.47. SD=1.01). 3. The results comparing stress with demographic variables were significant for gender (t=7.010. p=0.000). grades at school (F=2.918. p=0.02l), degree of obesity (F=5.205. p=0.006). grades (F=2.550. p=0.027). standard of living(F=8.277. p=0.000). the state of health (F=2.882, p=0.022), relationship with the father (F=4.790, p=0.001), relationship with the mother (F=6.080, p=0.000), and the educational level of the father (F=3.192, p=0.013). 4. The results comparing the coping method with demographic variables were significant for gender (t=4.597. p=0.000). These findings contribute to the understanding of the degree of stress and the type of coping methods of obese students in middle and high schools. Therefore, the result of this study aids in an effective nursing intervention to improve the mental health program for the obese.

  • PDF

An Observational Study on the Change of Micro-meteorological Environment due to Deforestation (삼림파괴로 인한 미기후 환경변화에 관한 관측적 연구)

  • Lim, Jung-Sub;Lee, Bu-Yong;Kim, Hae-Dong;Kim, Hak-Yoon;Hwang, Soo-Jin
    • Journal of the Korean earth science society
    • /
    • v.30 no.2
    • /
    • pp.185-195
    • /
    • 2009
  • We investigated the change of several meteorological variables due to deforestation. We established two sets of automatic weather observation system: one on a hill where forest was destructed by lumbering (Point 1) and the other in a neighboring district (Point 2) of fairly preserved forest. The observations were continued for one year (2006. 12-2007. 12). In this study, we analysed the data observed for one week from the nea day after summertime rainfall. The results showed that the air temperatures of Point 1 were about $1.5^{\circ}C$ higher than those of Point 2 during the daytime. But there were small gaps between the two poults during the nighttime. The relative humidities also differed greatly between the two during the daytime. It was as high as about 10% at Point 2. The surface and underground (15 cm in depth) soil temperatures were also fealty different between the two points during the daytime. They were $3-10^{\circ}C$ higher at Point 2 than those of Point 1. And the gaps reduced drastically during the nighttime. The averaged soil moistures were 7.1% at Point 1 and 19.5% at Point 2 during the observation period, respectively. The differences of wind direction were small, but the wind speeds differed between the two points. The observed wind speeds during the observation period were roughly estimated to be about 0.5m/s at Point 1 and 0.3m/s at Point 2. The heat budget analysis was also performed based on the observation data.

Assessment for Inhalation Exposure to Trihalomethanes (THMs) and Chroline and Efficiency of Ventilation for an Indoor Swimming Pool (일개 실내수영장의 공기 중 염소 및 트리할로메탄의 노출평가 및 환기 효율 평가)

  • Park, Hae-Dong;Park, Hyun-Hee;Shin, Jung-Ah;Kim, Tae-Ho
    • Journal of Environmental Health Sciences
    • /
    • v.36 no.5
    • /
    • pp.402-410
    • /
    • 2010
  • The objectives of this study were to evaluate the air quality surrounding an indoor swimming pool, to estimate the cancer risk based on the airborne exposure to trihalomethanes (THMs), and to examine the ventilation efficiency by Computational Fluid Dynamics (CFD). Chlorine and THMs were measured poolside, and in the staff room and reception area. The indoor swimming pool was modeled using the Airpak program, with ventilation drawings and actual survey data. Temperature, flow and mean age of the air were analyzed. Levels of chlorine poolside, and in the staff room, and reception area were $203\;{\mu}g/m^3$, $5\;{\mu}g/m^3$, and $10\;{\mu}g/m^3$, respectively. Chloroform was the dominant THM in all sampling sites and mean concentrations were $16.30\;{\mu}g/m^3$, $0.51\;{\mu}g/m^3$, and $0.06\;{\mu}g/m^3$ poolside, in the staff room and reception area, respectively. Bromodichloromethane and Dibromochloromethane levels were respectively estimated as $10.3\;{\mu}g/m^3$ and $1.7\;{\mu}g/m^3$ poolside, $1.3\;{\mu}g/m^3$ and $0.1\;{\mu}g/m^3$ in the staff room, and were not detected in the reception area. The cancer risks from inhalation exposure to THMs were estimated between $3.37{\times}10^{-7}$ and $1.84{\times}10^{-5}$. A short circulation phenomenon was observed from the supply air vents to the exhaust air vents located in the ceiling. A high temperature layer was formed within one meter of the ceiling, and a low temperature layer was formed under this layer due to the low velocity and high temperature of the supply air, and the improper locations of the supply air vents and exhaust air vents. The stagnation was evident at the above adult pool and the mean age of the air was 22 minutes. Disinfection by-products in the indoor swimming pool were present in higher concentrations than in the outdoor air. In order to increase the removal of pollutants, adjustment was required of the supply air volume and the supply/exhaust position.

A Cross-sectional Study between Herbal Medicine Intake and Abnormal Liver Function Test Results (간기능검사이상의 위험요인으로써 한약복용영향에 관한 단면연구)

  • Park, Hae-Mo;Shin, Heon-Tae;Park, Cheol-Soo;Lee, Sun-Dong
    • Journal of Society of Preventive Korean Medicine
    • /
    • v.12 no.2
    • /
    • pp.61-72
    • /
    • 2008
  • Objectives : The aim of this study was to evaluate effects of herbal medicine and other associated factors for abnormal liver function tests(especially total bilirubin, AST, ALT, and ${\gamma}$GT) levels in outpatients at an oriental medical clinic. Methods : A cross-sectional study based on clinical records was conducted on 504 patients at one Oriental medical clinic in Seoul, Korea. They were tested a liver function tests for screening and 497 patients ranging from the age of 4 to 74 were chosen for the study. Patients with basal liver disease or DM were excluded during the screening process. Patients were classified into case(abnormal) and control(normal) groups by normal liver function test references. Results and Conclusions : In this study, Significant correlations for abnormal total bilirubin levels was age, for abnormal AST was gender, for abnormal ALT were gender, smoking, marriage status, and job, for abnormal ${\gamma}$GT were age, gender, obesity, alcohol, smoking, marriage status, and job using the Chi-square test(p<0.05). There was no significant correlations for abnormal LFTs by using herbal medication history, and intake duration. After controlling other covariates, logistic regression analysis showed that the significant associated factors for abnormal total bilirubin levels were age(odds ratio[OR]=0.87, 95% confidence intervals [CI]=0.87-0.99). For abnormal AST levels was obesity(OR=2.45, CI=1.2-4.9), for abnormal ALT levels were age(OR=1.01, CI=0.99-1.03), male gender(OR=3.31, CI=1.62-6.76), and obesity(OR=3.71 CI=2.28-6.08). For abnormal ${\gamma}$GT levels were male gender(OR=4.83 CI=1.34-17.43), obesity(OR=3.29, CI=1.74-6.22), alcohol (OR=2.51, CI=1.19-5.28), and smoking(OR=2.29, CI=1.16-4.50). Herbal medication history was not as a risk factor for all abnormal liver function tests. Therefore, people who are male, obese, alcohol drinker and smoker will have higher liver function test levels. But intake of herbal medication or the duration of intake may not be the risk factor for abnormal liver function test results.

  • PDF

Toxicological Effect of Samultang (Herbal Medicine) Administration in the Pregnant Rats and Fetuses - Focusing on dose-response Relationship - (사물탕의 용량별 투여가 임신 랫드와 태자에 미치는 독성학적 연구)

  • Jeon, Sung-Jin;Shin, Heon-Tae;Kim, Kyung-Tae;Park, Hae-Mo;Lee, Sun-Dong
    • Journal of Society of Preventive Korean Medicine
    • /
    • v.14 no.3
    • /
    • pp.1-12
    • /
    • 2010
  • Objective : Samulatang (herbal description) is much used for women's disease in Korean Traditional Medicine. The aim of this study is to evaluate reproductive toxic effect by Samultang in pregnant rats and fetuses, and ascertain a dose-response relationship Method : Pregnant Sprague-Dawley rats were administered with the Samultang at single, double and quadruple dose for 20 days, orally. Pregnant rats were sacrificed at 20th day of gestation, and observed internal and reproductive organs. Live fetuses of gestation were randomly selected and fixed in 95% ethanol. Fetuses were stained with alcian blue and alizarin red S. We observe maternal body weight,, index associated pregnancy, and skeletal malformations in fetus Result : Maternal body weight of Samultang treated group has increased, side effect was not found in maternal body compared to that of control group. There were no significant difference in internal and reproductive organs. Double concentration administered group had lowest value in number of implantation, live fetuses, implantation rate and delivery rate, Also double concentration administered group showed higher early and late resorption rate than the other group. But, these are not significant. In the sex ratio, number of females, bigger than number of males in all Samultang administered groups. The fetuses of dams treated with Samultang didn't showed external and skeletal malformation. Vertebral and sternal variations were observed in single, double and quadruple concentration administered group but, compared to the control, those variations were insignificant. There were no significant changes in number of ribs, cervical, thoracic, lumber, sacral and caudal vertebrae Conclusion : Samultang is not expected to affect on pregnant rats and fetus about maternal body weight and number of live fetuses. There were no significant changes in organ weight, reproductive organs. Although skeletal variations were showed in vertebrae and sternum, treated groups were shown insignificant changes in skeletal variation

Cytoprotective Effects of Polyamines Against Oxidative Stress (산화 스트레스에 대한 폴리아민의 세포보호 효과)

  • Ahn Seoni;Lee Ji Young;Chung Hae Young;Yoo Mi-Ae;Kim Jong-Min;Kim Byeong Gee
    • Journal of Life Science
    • /
    • v.15 no.4 s.71
    • /
    • pp.626-632
    • /
    • 2005
  • The polyamines are essential components of all eukaryotic cells and absolutely necessary for cell growth. In the present study, the cytoprotective role of polyamine was characterized. When $Ac_2F$ rat liver cells were treated with 1M 2,2'-azobis (2-amidinopropane) dehydrochloride (AAPH), a water soluble free radical initiator, viability of the cells was noticeably decreased due to the increase of reactive oxygen species (ROS). The cytotoxic effect of AAPH as well as ROS generation were significantly inhibited by the treatment of polyamines. Among polyamines, especially spermine at $20{\mu}M$ concentration exerted over $45\%$ inhibition of AAPH-induced ROS generation. Western blotting was performed to determine whether superoxide dismutase(SOD) or catalase (CAT) expression was involved in oxidative stress. The AAPH treatment blocked both SOD and CAT protein expressions. Spermine could recover those protein expressions to the untreated control levels. According to the result of cycline E measurement, AAPH might block the entry of the cells into S phase of the cell cycle. The reduced expression of cyclin E protein could be fully recovered by the addition of spermine. The antioxidative effects of spermine was also further proved by the apopotitic morphological analysis using ethidium bromide and acridine orange.