• Title/Summary/Keyword: Higher Concentration

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Pilot Study for Difference of Secondhand Smoke Exposure at Smoking and Non-smoking Nightclubs (흡연과 금연 나이트클럽의 간접흡연 노출의 차이에 대한 탐색연구)

  • Guak, Sooyoung;Lee, Boram;Xu, Siyu;Lee, Kiyoung;Lee, Dohoon
    • Journal of Environmental Health Sciences
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    • v.40 no.1
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    • pp.10-16
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    • 2014
  • Objectives: This pilot study assessed secondhand smoke (SHS) exposure in smoking and non-smoking nightclubs in Seoul, Korea by measuring the concentration of particulate matter smaller than $2.5{\mu}m$ ($PM_{2.5}$). Methods: This comparative study was conducted in three nightclubs in Seoul. While one non-smoking nightclub was measured on weekdays and weekends, different smoking nightclubs were measured on weekdays and weekends. The concentration of $PM_{2.5}$ was observed using a real-time monitor over an average of three hours. The number of people in the clubs was also estimated. Settled dust was collected in a smoking and a non-smoking nightclub and analyzed for NNK concentration. Results: The $PM_{2.5}$ concentration in the smoking nightclubs was higher than those found in the non-smoking nightclub by 26 times on weekdays and three times on weekends. Indoor $PM_{2.5}$ concentration was correlated with the number of people in the smoking nightclubs. Relatively high $PM_{2.5}$ concentration was observed in the non-smoking nightclub on weekends. NNK concentration in the smoking nightclub was 7 times higer than in the non-smoking nightclub. Conclusion: Smoking in nightclubs caused high $PM_{2.5}$ concentration. Although the non-smoking nightclub had a lower $PM_{2.5}$ concentration, $PM_{2.5}$ concentration on weekends was higher due to the smoking room. Complete prohibition of smoking in nightclubs can protect patrons from secondhand smoke exposure.

The joint effect of different concentration of Cd2+ and ionic liquid on the growth of wheat seedlings

  • Chen, Zhonglin;Zhou, Qian;Leng, Feng;Dai, Bing;Zhao, Xueyang;Zhang, Weichen;Liu, Neng;Guan, Wei;Liu, Kui
    • Environmental Engineering Research
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    • v.22 no.3
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    • pp.281-287
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    • 2017
  • The joint effect of different concentrations (0.05-0.375 mmol/L) of $Cd^{2+}$ and various concentrations (50-400 mg/L) of [$C_3mim$][OAc] on the growth and physiology of wheat seedlings were investigated. The toxicity of $Cd^{2+}$ could be significantly reduced by lower concentrations (50-200 mg/L) of [$C_3mim$][OAc]. With higher concentration (${\geq}300mg/L$) of [$C_3mim$][OAc], the reduction became less, and compared to $Cd^{2+}$ stress only, the toxicity of 400 mg/L [$C_3mim$][OAc] increased. As for different $Cd^{2+}$ concentrations, the optimal reduction depends on the balance between the exact concentration of $Cd^{2+}$ and [$C_3mim$][OAc]: With low $Cd^{2+}$ concentration (0.05-0.250 mmol/L) requiring 50 mg/L [$C_3mim$][OAc], it could reach a dynamic equilibrium, while high $Cd^{2+}$ concentration (0.375 mmol/L) requiring 100 mg/L [$C_3mim$][OAc]. The growth and physiological indexes of wheat seedlings show a decrease in toxicity compared to the Cd alone treatment, when the dynamic equilibrium is reached. The concentration of $Cd^{2+}$ in leaf tissues showed that low concentration (50-200 mg/L) of [$C_3mim$][OAc] can reduce the toxicity of $Cd^{2+}$ (0.05-0.375 mmol/L) by decreasing the level of $Cd^{2+}$ concentration in the tissues, whereas the higher concentration (${\geq}300mg/L$) of [$C_3mim$][OAc] can increase the concentration of $Cd^{2+}$.

Assessment of Formaldehyde Concentration in Indoor and Outdoor Environments of Schools in Incheon (인천지역 일부 학교의 실내 및 대기 중 포름알데히드 농도 평가)

  • Jeung, Yeon-Hee;Choi, Sang-Jun
    • Journal of Environmental Health Sciences
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    • v.33 no.5
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    • pp.372-378
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    • 2007
  • This study evaluated formaldehyde concentration in classrooms and on roofs at 4 elementary schools, 3 middle schools and 3 high schools in Incheon City. These schools were chosen based on their surrounding environments that included industrial site, landfill, railway, 8-lane road and harbor. Indoor concentration ranged between 4.65 and $56.25{\mu}g/m^3$, while that of outdoor concentration was $1.23{\sim}10.22{\mu}g/m^3$, both of which were below $100{\mu}g/m^3$, a formaldehyde criterion stipulated by the School Health Act. Indoor concentration was higher than outdoor concentration by $1.4{\sim}5.9$ times, and there was a positive correlation between indoor and outdoor formaldehyde concentrations (R=0.49). As for indoor concentration, multi-use practice rooms had an average 2.8 times higher than that of usual classrooms with a statistically significant difference (p<0.01). Indoor formaldehyde concentration had a positive correlation with the construction year (R=0.55). The school close to the industrial complex had the highest ambient formaldehyde concentration, followed by the one near a landfill. The formaldehyde concentration in school in the vicinity of the industrial complex was twice or more than that of the school located other site. In conclusion, this study suggests that it is crucial to consider surrounding environments in selecting school sites, as it can influence ambient air contamination, as well as using construction material that emit less formaldehyde, in order to protect the health of students, teachers and school staff.

A Study of The Relationship between Alcohol Intake, Smoking, Relative Weight and Serum Lipids Level in Young Adult Male Workers (젊은 성인 남자 근로자들에 있어서 음주, 흡연, 비만도와 혈중 지질과의 관련성에 관한 조사 연구)

  • Lee, Ji-Ho;Cho, Byung-Mann;Lee, Soo-Ill;Kim, Don-Kyoun
    • Journal of Preventive Medicine and Public Health
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    • v.25 no.4 s.40
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    • pp.386-398
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    • 1992
  • In order to study the relationship between life-style and serum lipids level in young adults, the author measured the concentration of serum total cholesterol (TC), triglyceride (TG) and high density lipoprotein cholesterol (HDL-C) and investigated age, relative weight, weekly alcohol intake and daily cigarette smoking through questionnaire in 310 male workers aged 20 to 39, in Ulsan area. The results obtained were as follows: 1. In the factors being able to influence serum lipids level there was negative correlation between age and alcohol intake, and the positive correlation between age and relative weight, alcohol intake and relative weight, alcohol intake and smoking with the strongest correlation between alcohol intake and smoking. 2. In univariate analysis, mean total cholesterol concentration were significantly different according to age, smoking and relative weight: mean triglyceride concentration were significantly different according to relative weight only; mean HCL-C concentration were significantly different according to alcohol intake alone. 3. In non-drinkers, HDL-C concentration of smokers were significantly lower than that of non-smokers but triglyceride concentration of smokers were significant higher. And in drinkers, total cholesterol concentration of smokers was significantly higher than that of non-smokers. 4. In multiple regression analysis, significant independent variables were relative weight, age and smoking in the total cholesterol concentration, and relative weight, age and alcohol intake in the triglyceride concentration, and alcohol intake, relative weight and smoking in the HDL-C concentration. By these independent variables, total variation in each dependent variable was explained 7.9%, 17.6% and 7.4% respectively.

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Blood Mercury Concentration and Related Factors in an Urban Coastal Area in Korea

  • Jo, Eun-Mi;Kim, Byoung-Gwon;Kim, Yu-Mi;Yu, Seung-Do;You, Chang-Hun;Kim, Joon-Youn;Hong, Young-Seoub
    • Journal of Preventive Medicine and Public Health
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    • v.43 no.5
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    • pp.377-386
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    • 2010
  • Objectives: This study was carried out for the purpose of evaluating the blood mercury concentration of the residents of Busan, Korea, as well as the relationship between the mercury concentration and the pattern of fish consumption along with other epidemiological factors. Methods: Two hundred ninety-three subjects (147 men and 146 women), who were aged 40 years or more, were recruited into this study between June and October 2009. The mean age of the subjects was 54.3 years (with a range of 40-70 years). Mercury concentrations in blood samples were measured using a gold-amalgam collection method. Results: The geometric mean concentration of mercury in the total subjects was $8.63\;{\mu}g/L$ [range: $1.48{\sim}45.71\;{\mu}g/L$]. The blood mercury concentration of the men ($9.55\;{\mu}g/L$) was significantly higher than that of the women ($7.76\;{\mu}g/L$). The blood mercury concentration of those who eat fish more than 4 times per week was higher than others, and was statistically significant (male p = 0.0019, female p = 0.0002). According to the multiple analysis, the blood mercury concentration was significantly affected by the consumed fish but other epidemiological factors were not related. Conclusions: It was found that the subjects who have consumed a large amount of fish may have high blood mercury concentration. It appears that fish consumption can influence blood mercury concentration. Therefore, guidelines for fish consumption that will decrease blood mercury concentration might be necessary in Korea.

Effect of Triton X-100 on Compactin Production from Penicillium citrinum

  • Park, Du-Bok;Cho, Ki-An;Cha, Wol-Suk;Ryu, Seong-Ryeol
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.9 no.3
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    • pp.171-178
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    • 2004
  • Glucose alone was found to be the most effective carbon source for producing compactin. An initial glucose concentration of 40 g/L gave the highest compactin concentration of 250mg/L. Among the various nitrogen sources, when 5g/L of pharmamedia and soybean meal as the sole nitrogen source were used, respectively, the compactin concentration was higher than 250mg/L. Especially, in the case of the mixture of 6 g/L of pharmamedia and 8 g/L of soybean meal, the compactin concentration was 400mg/L. To select the best surfactant for effective compactin production, various surfactants were investigated. When Triton X-100 was used, the maximum compactin concentration was 445mg/L. With the initial concentration ranging from 1.5 to 2.0 g/L, the compactin concentration was the highest at 465-450mg/L. The cell concentration was similar to that of the control without the addition of Triton X-100. On the other hand, when the above 4.0 g/L of Triton X-100 were used, the cell concentration decreased. Using the based results, the continuous fed-batch cultures by adding the Triton X-100 were carried out for 10 days in an air-lift bioreactor. When 1.5 g/L of Triton X-100 was added to the culture broth at 0, 4, and 8 days of culture, respectively, the compactin production was increased with the increase of culture time. The maximum compactin concentration after 10days of culture was 1,200mg/L, which was about 2.0-fold higher than that of the control without the addition of Triton X-100.

Study on Motility and Acrosome Morphology of Fresh and Deep-frozen Korean Native Goat Spermatozoa (액상 및 동결보존된 한국재래산양 정자의 운동성 및 첨체형태에 관한 연구)

  • 황덕수;양문한;이규승;박창식
    • Korean Journal of Animal Reproduction
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    • v.13 no.1
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    • pp.18-25
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    • 1989
  • This study was carried out to investigate the general semen characteristics of the Korean native goat and the effect of temperature, incubation time, dilution rate, freezing rate and glycerol concentration on motility and NAR (normal apical ridge) acrosome of fresh and frozen Korean native goat spermatozoa. 1. Average semen volume per ejaculate, motility, concentration and pH of fresh Korean native goat spermatozoa were 0.19${\pm}$0.09 ml, 94.5${\pm}$0.47%, 26.17${\times}$108${\pm}$1.68/ml and 6.63${\pm}$0.18, respectively. 2. Motility and NAR acrosome of fresh spermatozoa during incubation were higher at 22$^{\circ}C$ than at 5$^{\circ}C$ or 37$^{\circ}C$(P<.01). 3. Motility and NAR acrosome of spermatozoa diluted 1:4 during incubation were higher at 22$^{\circ}C$ than at 5$^{\circ}C$ or 37$^{\circ}C$(P<.01). 4. Motility and NAR acrosome of spermatozoa during incubation were higher for samples diluted 1:1, 1:2, or 1:4 than for samples diluted 1:6(P<.01). 5. Motility and NAR acrosome of post-thaw spermatozoa were higher at freezing rate of 12$^{\circ}C$/min than at freezing rate of 1$^{\circ}C$/min or 24$^{\circ}C$/min when glycerol concentration was 9%(P<.01).

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A Comparison of Anthropometry and Iron Status in Children Provided with and without Natinoal School Lunch Program (급식교와 비급식교 아동의 성장발달 및 철분영양상태 비교)

  • 김은경
    • Journal of Nutrition and Health
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    • v.30 no.8
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    • pp.1009-1017
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    • 1997
  • This study was designed to assess the iron nutritional status and growth development of children provided with and without the national school -lunch program(NLSP). The subjects consisted of 590 elementary school children (313 boys, 277 girls) in the 2nd, 4th and 6th grades provided with (n=390) and without (n=200) NSLP. anthropometric measurements were taken for body weight, height, triceps skinfold thickness and body fat percentage. Nutrient intakes were assessed by a modified 24 -hour recall method. Fastinig blood samples were obtained and analyzed for hemoglobin concentration, hematocrit, serum iron and total iron binding capacity. The results obtained are summarized as follows. No significant differences between children provided with and without NSLP were found in height and body weight, but triceps skinfold thickness and body fat(%) were significantly higher in children without NSLP than in those with NSLP. There was no significant difference in hemoglobin concentration and hematocrit between children provided with and without NSLP. However, serum iron concentration and transferrin saturation were higher in the children provided with NSLP(81.9$\mu\textrm{g}$/dl and 22.8%) than in the children without NSLP(73.1$\mu\textrm{g}$/dl and 20.9%). When comparing iron and vitamin C intakes , iron intake was significantly higher in children provided with school-lunch, but vitamin C intake was significantly higher in children provided without school-lunch. Percentages of iron -deficient anemia in underweight, normal and obese children when judged by total iron binding capacity were 14.9%, 12.5% and 25.8% respectively.

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Comparison of Acid and Phenol Compounds in Smoke Total Particulate Matter by the Different Tobacco Leaves (잎담배 종류 및 등급에 따른 담배 연기응축물의 Acid 및 Phenol 화합물 함량 비교)

  • 황건중;이문수;나도영;장기철
    • Journal of the Korean Society of Tobacco Science
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    • v.22 no.1
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    • pp.84-90
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    • 2000
  • This study was conducted to determine the acid and phenol compounds in smoke total particulate matter(TPM) by the different tobacco variety, and grade of tobacco leaves. Sixteen kinds of tobacco leaves which were flue-curd, burley, orient, reconstituted tobacco, expanded stem, and expanded cut tobacco, were selected for this study. After collecting a TPM by using smoking machine, the concentration of TPM components was analyzed by GC. Acid components of TPM of mainstream smoke were different from the variety and grade. The order of the highest concentration of acid compounds in TPM was flue-cured > orient> burley> expanded cut tobacco> reconstituted tobacco> expanded stem. Though lactic acid and glycolic acid concentrations in flue-cured tobacco were twice higher than those in burley tobacco, the contents of 2-furoic acid and 3,4-dihydroxy butanoic acid in burley tobacco were higher than those in flue-cured tobacco. The content of phenolic compounds in the high grade and thick leaves was higher than that in other tobacco leaves. Phenol and catechol compounds in burley CD3W-2 revealed the least value in concentration among the samples tested. Pyrocatechol and hydroquinone concentrations in flue-cured tobacco were 2-3 times higher than those in burley and orient tobacco.

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The Study of Lead Concentration in Maternal and Umbilical Cord Blood (산모 혈액과 탯줄 혈액의 연(鉛)함량에 관한 연구)

  • Kim, Dong-Jun;Kim, Myung-Hee;Chung, Ae-Soon;Kang, Shin-Myung
    • The Korean Journal of Physiology
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    • v.11 no.2
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    • pp.63-66
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    • 1977
  • Motor vehicles are the major source of environmental air pollution through the combustion of lead-containing gasolines. People who live in the areas with heavy traffic usually have the higher blood lead levels. This study was to investigate the lead level between the maternal blood and their infants cord blood. Immediatly after Placental delivary, the sampls of cord blood and maternal venous blood were obtained randomly from 14 infants whose mothers had spent their entire pregnancy in Seoul. Lead concentration was determined by the dithizone method. The results obtained were summarized as follows: 1. Hemoglobin, Hct and RBC were significantly higher in cord blood than in the maternal blood, by 36%, 54.9%, 36.9% respectively. 2. MCV in cord blood was higher than that in maternal blood by 13.8%. But MCH and MCHC were lower than those in maternal blood, by 9.7%, 3.3% respectively. The differences were statistically significant. 3. Lead concentration of cord blood $(23.93\;{\mu}g%)$ was higher than that in maternal blood $(21.93\;{\mu}%)$ by 9.1%.

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