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A Study on the Normal Values of Lead Exposure Indices (연폭로 지표들의 정상치에 관한 연구)

  • Shin, Hai-Rim;Kim, Joon-Youn
    • Journal of Preventive Medicine and Public Health
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    • v.19 no.2 s.20
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    • pp.167-176
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    • 1986
  • For the purpose of determinating the normal values of some parameters relevant to lead exposure, a study was carried out from April 1 to June 30, 1986 on 258 healthy Korean adults who have had no apparant lead exposure. The lead indices subjected to this study were as follows; blood lead (PbB), hemoglobin (Hb), zinc protoporphyrin in blood (ZPP), delta-aminolevulinic acid dehydratase (ALAD) activity in blood, coproporphyrin in urine (CPU), delta-aminolevulinic acid in urine (ALAU). 1) The mean value of PbB was $17.17{\pm}7.87{\mu}g/100ml$, and there was no statistically significant difference by age & sex. The distribution of PbB fitted to the log-normal distribution ($x^2=7.38$, p>0.1). 2) The mean value of Hb in male ($15.17{\pm}1.56g/100ml$) was higher than in female ($13.22{\pm}1.51g/100ml$)(p<0.01). The distribution of Hb fitted to the normal distribution ($x^2=9.40$, p>0.1). 3) The mean value of ZPP was $32.61{\pm}8.78{\mu}g/100ml$, and there was no statistically significant difference by age & sex. The distribution of ZPP fitted to the normal distribution ($x^2=13.93$, p>0.05). The correlation of ZPP & ALAD (r=-0.229), CPU (r=0.183) was statistically significant respectively. 4) The mean value of ALAD was $30.20{\pm}10.96{\mu}mol$ ALA/min/L of R.B.C., and there was no statistically significant difference by age & sex. The distribution of ALAD activity did not fit to the normal distribution. The correlation between ALAD & PbB (r=-0.219) was statistically significant 5) The mean value of CPU was $36.10{\pm}24.54{\mu}g/L$, and there was no statistically significant difference by age & sex. The distribution of CPU did not fit to the normal distribution. The correlation between CPU & PbB (r=0.185), ZPP (r=0.183) was statistically signinificant respectively. 6) The mean value of ALAU was $1.94{\pm}0.96mg/L$, and there was no statistically significant difference by age & sex. The distribution of ALAU fitted to the normal distribution ($x^2=9.76$, p>0.1).

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Study on the lead exposure of workers in a litharge making industry (모 일산화 연 제조 업체 근로자들의 연 폭로에 관한 연구)

  • Lim, Sang-Bok;Lim, Jung-Kyu;Lee, Sung-Soo;Ahn, Kyu-Dong;Lee, Byung-Kook
    • Journal of Preventive Medicine and Public Health
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    • v.28 no.4 s.51
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    • pp.875-884
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    • 1995
  • In order to investigate the level of lead exposure of workers in litharge making industry and to evaluate how lead exposure, personal habit such as smoking and drinking affect the prevalence of lead related symptoms and other study variables, we investigate 114 workers(24 office workers and 90 lead exposed workers) in a litharge making industry. Study variables chosen were blood lead(PbB), zinc protoporphyrin in whole blood(ZPP), Hemoglobin(Hb), hematocrit (Hct), SGOT and SGPT symptom questionnaires which had 15 lead exposure related symptoms were provided to all workers and filled up by themselves and reconfirmed by physician. The results obtained were as follows; 1. The mean value of PbB, ZPP and SGOT in lead exposed group were higher than those of non-exposed group, and there were no differences of means in other study variables. 2. The smoking and drinking rate of study subjects were 65.8% and 71.0% as a whole. Smoking rates were lower in non-exposed group than exposed group, but drinking rate were not. 3. There were no differences of mean values of study variables between smoker and non-smoker in non-exposed and exposed group, but there was a difference of mean value of SGOT between drinker and lion-drinker in lead exposed group. 4. While the symptom prevalence of lead exposed group were higher in neuromuscular category than non-exposed group, those of non-exposed group were higher or same with exposed group in gastrointestinal and general symptom category. 5. The symptom prevalence of smoker were higher than non-smoker regardless of exposure. 6. The symptom prevalence of drinker were only higher in gastrointestinal symptom category than non-drinker. 7. In multiple stepwise regression analysis of lead related symptoms as dependent variable and blood lead, smoking habit, drinking habit and work duration as independent variables, drinking habit contributed to the gastrointestinal symptom category, whereas blood lead and smoking contributed to the neuromuscular symptom category. For the total symptoms work duration and smoking habit contributed significantly.

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Molecular Sex Determination Using Sexual Dimorphisms between ZFX and ZFY Genes in Korean Hares(Lepus coreanus Thomas) (한국멧토끼 ZFX와 ZFY 유전자의 성별 이형성과 분자 성판별)

  • Han, Sang-Hyun;Cho, In-Cheol;Lee, Sung-Soo;Oh, Moon-You;Oh, Hong-Shik
    • Journal of Life Science
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    • v.17 no.3 s.83
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    • pp.402-406
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    • 2007
  • This study was performed to develop the molecular marker for sex determination of hare (Lepus coreanus) distributed in Korea which focused on sexual dimorphism between X and Y chromosomal homologous genes, zinc finger-X (ZFX) and -Y (ZFY). The intron 7 regions of ZFX and ZFY genes exhibited differential amplification patterns between male and female hares. The lengths of intron 7 region of ZFX and ZFY genes were 538 and 233-bp, respectively. Especially, the ZFX intron 7 contained a repetitive sequence identified as member of RNA-mediated transposable elements which was similar to CSINE2 commonly found in the rabbit genome. However, it was not present in intron 7 of ZFY gene. The molecular sex typing by polymerase chain reaction (PCR) was also carried out to determine the sex of hare based on difference in lengths between the intron 7 regions of ZFX and ZFY genes. All DNA samples tested had common band amplified from ZFX. However, the male hare DNAs had two distinct bands which amplified from ZFX and ZFY genes, respectively. The results from ZFX-ZFY PCR sex typing were identical to those from phenotypic investigation and from amplification patterns using male-specific sex determining region Y (SRY) gene as well. Finally, this study suggested that the sexual dimorphism between intron 7 regions of ZFX and ZFY could be useful genetic marker to determine sex of hare.

Strategies for Development of Seafloor Polymetallic Sulphides in Consideration of International Progress (해저열수광상 개발동향과 우리나라의 대응방안)

  • Park, Seong-Wook;Yang, Hee-Cheol;Jeong, Hyeong-Su
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.13 no.3
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    • pp.271-279
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    • 2008
  • Polymetallic sulphides means hydrothermally formed deposits of sulphide minerals which contain concentrations of metals including, inter alia, copper, lead, zinc, gold and silver. Nautilus is the first company to commercially explore the seafloor polymetallic sulphide deposits. The Company holds exploration licences and exploration applications for more than 370,000 $km^2$ in the jurisdictional seas of Papua New Guinea, Fiji, Tonga, the Solomon Islands and New Zealand along the western Pacific Ocean's Rim of Fire. Neptune Minerals is also a leading explorer and developer in this field, with exploration licences awarded totalling more than 270,000 $km^2$ in the territorial seas or EEZ of New Zealand, Papua New Guinea and the Federated States of Micronesia. These two companies now carry out the most active investment activities for seafloor polymetallic sulphide deposits with a goal of commercial production by 2010. China and Japan carry out exploration activities for the seafloor polymetallic sulphide deposits to secure supplies of strategic metals. China carries out national R&D projects relating to deep sea mineral resources in the world ocean through China Ocean Mineral Resources R&D Association(COMRA). And Japan investigates her own EEZ for exploration of the seafloor polymetallic sulphide deposits. In consideration of aforementioned international activities of coastal nations as well as private companies for exploring the sulphide deposits, Korea shall prepare strategic plans : First, consolidation of the authorities concerned and legislative support; second, determination of main entity of the project; third, securing government's decisive investment of sufficient budget; and lastly, establishment of the mid, long-term plan for development of seafloor polymetallic sulphides deposits.

Establishment of Marine Ecotoxicological Standard Method for Larval Fish Survival Test (어류 자어의 사망률을 이용한 해양생태독성시험 방법에 관한 연구)

  • Park, Gyung-Soo;Kang, Ju-Chan;Yoon, Sung-Jin;Lee, Seung-Min;Hwang, Un-Ki
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.13 no.2
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    • pp.140-146
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    • 2008
  • Marine ecotoxicological standard method using fish larvae was established with the standard test species of Oryzias latipes(Japanese Medaka) and Paralichthys olivaceus(flounder) and with the 7 day $LC_{50}$ as endpoint. Test method referred to the USEPA(1994) with the replacement of test species found in the Korean water. Standard test species were selected in terms of the species supply and ecological importance in Korean waters. Japanese medaka can be reared with small tanks in the lab and has wide tolerance on salinity, and flounder eggs can be easily obtained from commercial fish hatcheries. General conditions for larval fish toxicity test are as follows. The possible salinity ranges for toxicity test were $0{\sim}35\;psu$ for medaka and >20 psu for flounder. Test type was designated as static non-renewal test if the dissolved oxygen in the test chamber does not fall below 4.0 mg/L. Ages of test species were selected as 7 days after hatched for medaka(about 5 mm TL) and 25 days for flounder(about 10 mm TL) because of the low natural mortality after these periods. Test can be accepted when the survival rates are over 80% in control. Also, species sensitivity on standard reference materials(copper, cadmium or zinc) must be provided with the toxicity test results.

Growth of Chrysanthemum Cultivars as Affected by Silicon Source and Application Method

  • Sivanesan, Iyyakkannu;Son, Moon Sook;Soundararajan, Prabhakaran;Jeong, Byoung Ryong
    • Horticultural Science & Technology
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    • v.31 no.5
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    • pp.544-551
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    • 2013
  • The effect of different silicon (Si) sources and methods of application on the growth of two chrysanthemum cultivars grown in a soilless substrate was investigated. Rooted terminal cuttings of Dendranthema grandiflorum 'Lemmon Eye' and 'Pink Eye' were transplanted into pots containing a coir-based substrate. A nutrient solution containing 0 or $50mg{\cdot}L^{-1}$ Si from calcium silicate ($CaSiO_3$), potassium silicate ($K_2SiO_3$) or sodium silicate ($Na_2SiO_3$) was supplied once a day through an ebb-and-flood sub irrigation system. A foliar spray of 0 or $50mg{\cdot}L^{-1}$ Si was applied twice a week. Cultivar and application method had a significant effect on plant height. Cultivar, application method, and Si source had a significant effect on plant width. Of the three Si sources studied, $K_2SiO_3$ was found to be the best for the increasing number of flowers, followed by $CaSiO_3$ and $Na_2SiO_3$. In both the cultivars, sub irrigational supply of Si developed necrotic lesions in the older leaves at the beginning of the flowering stage as compared to the control and foliar spray of Si. Cultivar, application method, Si source, and their interactions had significant influence on leaf tissue concentrations of calcium (Ca), potassium (K), phosphorus (P), magnesium (Mg), sulfur (S), sodium (Na), boron (B), iron (Fe), and zinc (Zn). The addition of Si to the nutrient solution decreased leaf tissue concentrations of Ca, Mg, S, Na, B, Cu, Fe, and Mn in both cultivars. The greatest Si concentration in leaf tissue was found in 'Lemmon Eye' ($1420{\mu}g{\cdot}g^{-1}$) and 'Pink Eye' ($1683{\mu}g{\cdot}g^{-1}$) when $K_2SiO_3$ was applied through a sub irrigation system and by foliar spray, respectively.

Study on Nutritive Value and In Situ Ruminal Degradability of Whole Crop Rice Silage Prepared Using Chucheongbyeo (추청벼 총체 사일리지의 사료가치 및 부위별 In situ 분해율에 관한 연구)

  • Ki, Kwang Seok;Park, Su Bum;Lim, Dong Hyun;Park, Seong Min;Kim, Sang Bum;Kwon, Eung Gi;Lee, Se Young;Choi, Ki Chon
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.33 no.4
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    • pp.240-244
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    • 2013
  • We investigated the nutritive value and ruminal in situ dry matter degradability of whole crop rice silage prepared using Chucheongbyeo (WCRS) as a roughage source for ruminants. The crude protein (7.54%), acid detergent fiber (29.63%), neutral detergent fiber (62.98%), and total digestible nutrient (TDN) (57.88%) found higher in WCRS than those of rice straw. Manganese content in the WCRS was the highest, followed by carbon, iron, zinc, and copper, but magnesium content was the lowest. Glutamic acid content in WCRS was the highest, followed by leucine, asparagine, alanine, valine, arginine, and methionine content was the lowest. We examined ruminal in situ digestibility from total whole crop rice (TWCR), rice husks containing rice (RHR), whole crop rice except RHR (WER), and husked grain (HG) for 3, 6, 12, 24, and 48 hours. Ruminal in situ digestibility in the HG was the highest, followed by RHR, TWCR, and WER. Therefore, we suggest that ruminal in situ degradability was influenced by parts of whole crop rice, and the content of manganese and glutamic acid were the highest in WCRS.

Physiological Effects of Casein-derived Bioactive Peptides (카제인 유래 생리활성 Peptide의 체내 효과)

  • Jung, Ho-Jung;Min, Bock-Ki;Kwak, Hae-Soo
    • Food Science of Animal Resources
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    • v.29 no.6
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    • pp.659-667
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    • 2009
  • Casein is considered to be the main source of protein in milk; therefore, many studies have been conducted to identify casein-derived bioactive peptides and their physiological effects. Casein is inactive within the parent protein but can be liberated by various proteases and enzymatic hydrolysis during microbial fermentation and gastrointestinal digestion. Once absorbed, casein exhibits different bioavailabilities in the body. Specifically, casein-derived peptides function as angiotensin converting enzyme (ACE) inhibitor in the cardiovascular system; thus, they are expected to reduce and prevent hypertension. Additionally, casein-derived peptides behave as opioid-like peptides in the nervous system, which impacts relaxation. These peptides are also expected to modulate various aspects of immune functions. Finally, caseinophosphopeptide (CPP) and glycomacropeptide (GMP) may exhibit a number of nutritional effects such as the absorption of calcium, iron or zinc. Many studies have been conducted to evaluate casein-derived peptides due to their multifunctional properties and the results of these studies have contributed to the development of a wide variety of functional dairy products. The purpose of this paper was to review the generation of bioactive peptides, their absorption and metabolism, and their specific bioactive effects.

Corrosion Analysis of Ni alloy according to the type of molten metal (용융아연도금욕에 적용되는 용탕에 따른 Ni합금의 부식성 분석)

  • Baek, Min-Sook
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.6
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    • pp.459-463
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    • 2017
  • Hot dip galvanizing in the steel plant is one of the most widely used methods for preventing the corrosion of steel materials including structures, steel sheets, and materials for industrial facilities. While hot dip galvanizing has the advantage of stability and economic feasibility, it has difficulty in repairing equipment and maintaining the facilities due to high-temperature oxidation caused by Zn Fume where molten zinc used in the open spaces. Currently, SM45C (carbon steel plate for mechanical structure, KS standard) is used for the equipment. If a part of the equipment is resistant to high temperature and Zn fume, it is expected to improve equipment life and performance. In this study, the manufactured Ni alloy was tested for its corrosion resistance against Zn fume when it was used in the hot dip galvanizing equipment in the steel plant. Two kinds of materials currently used in the equipment, new Ni alloy and Inconel(typical corrosion-resistant Ni alloy), were selected as the reference groups. Two kinds of molten metal were used to confirm the corrosion of each alloy according to the molten metal. Zn fume was generated by bubbling Ar gas from molten Zn in a furnace($500{\sim}700^{\circ}C$) and the samples were analyzed after 30 days. After 30 days, the specimens were taken out, the oxide layer on the surface was confirmed with an optical microscope and SEM, and the corrosion was confirmed using a potentiodynamic polarization test. Corrosion depends on the type of molten metal.

Influence of Maternal Diet on Mineral and Trace Element Content of Human Milk and Relationships Between Level of These Milk Constituents (수유부의 식이섭취가 모유의 무기질 및 미량원소 함량에 미치는 영향과 모유의 각 무기질 농도 사이의 상관성 연구)

  • 안홍석
    • Journal of Nutrition and Health
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    • v.26 no.6
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    • pp.772-782
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    • 1993
  • This study was conducted to assess the relationships between maternal dietary intakes and milk contents of minerals and trace elements, and the correlation among levels of these milk constituents. Maternal dietary intakes were measured and milk samples were collected at 2∼5 days, 2, 4, 6 and 12 weeks postpartum from 29 lactating women. The results obtained are sumarized as follows: 1) The overall mean nutrient intakes of lactating women in this study were below the recommended allowances and there were extensive individual variations between subjects. 2) Concentrations of minerals and trace elements in matured human milk showed the same range reported from different countries with the exception of calcium, magnesium, manganese and molybdenum which were relatively high. 3) There were no significant relationships between maternal dietary intakes of minerals and the corresponding mineral levels of human milk. In addition, no significant correlations were found between maternal vitamin C intake and the iron contents of milk. These were significant positive correlations between maternal calcium intake and the magnesium level of milk ; between maternal protein intake and the contents of zinc and copper in human milk. Maternal energy intake was negatively correlated with milk sodium level. 4) Pearson correlation coefficient showed positive significant relationships between levels of 17 pairs of various mineral and trace elements : sodium and potassium, iron ; potassium and calcium, phosphors, magnesium, iron, copper, manganese ; calcium and magnesium, iron manganese, molybdenm, nickel ; magnesium and iron, molybdenum ; iron and copper ; nickel and manganese.

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