• Title/Summary/Keyword: pCR

Search Result 1,869, Processing Time 0.028 seconds

A Study on Heavy Metal Contents of the Fresh Water Fish, and the Shellfish in Koran (국내 유통 민물어류와 연안산 패류의 중금속 함량에 관한 조사)

  • 김연천;한선희
    • Journal of Food Hygiene and Safety
    • /
    • v.14 no.3
    • /
    • pp.305-318
    • /
    • 1999
  • This study were conducted to estimate the values of the heavy metal in the fresh water fish and shellfish collected from fish market. The levels of the heavy metal were determined in a total of 319 samples of 11 species of the fresh water fish and 14 species of the shellfish by mercury analyzer and atomic absorption spectrophotometer. The results of this study were summerized as follows; The average contents of the heavy metal in the fresh water fish were Pb 0.075, Hg 0.05:3, Cd 0.002, Cr 0.135, Fe 8.695, Mn 1.078, Zn 9A91, Cu 0.548 mg/ kg. The average contents of the heavy metal in the shellfish were Pb 0.059. Hg 0.007, Cd 0.146, Cr 0.147, Fe 40.808, Mn 7.738, Zn 13.943, Cu 2.7:31 mg/kg. Being compared the average contents of the heavy metal of the fresh water fish with those of shellfish, the average contents of Cd, Fe, Mn, Cu in the shellfish were significantly higher than in the fresh water fish(P<0.001). Depending on the sampling areas, the average contents of the heavy metal were different by districts. The contents of the heavy metal were changed with the seasons(P<0.05).

  • PDF

Heavy Metal Concentrations in Tree Ring Layer and Soil and Tree Ring Growth of Roadside Trees in Seoul (서울시 가로수의 연륜층 및 식재주변 토양의 증금속 농도와 연륜 생장)

  • Yoo, Jae-Yun;Son, Yo-Whan
    • Korean Journal of Environmental Agriculture
    • /
    • v.22 no.2
    • /
    • pp.118-123
    • /
    • 2003
  • This study was carried out to examine the heavy metal concentrations in soils under roadside trees and tree ring layers, and to investigate the relationship between heavy metal concentrations and tree ring growth of roadside trees in Seoul. Soil samples at $0{\sim}20\;cm$ depth and tree line were collected from Platanus occidentalis and Ginkgo biloba at nine streets, and pH and heavy Metal concentrations were analyzed. Soil pH ranged from 6.62 to 8.01 and soil heavy metal concentrations under roadside trees were higher (Zn 109.03, Pb 26.49 and Cu 44.98 mg/kg) compared with those of the referred forest soils. Soils at Cheonggye2ga street showed the highest heavy metal concentrations, and seemed to be related to heavy traffic and dense hardware stores. Tree ring width significantly decreased from 1979 through 2000 for both species. There were positive correlations between Cr, Pb and Cu concentrations in soils and tree ring layers for P. occidentalis and Ni for G. biloba. However, there were negative correlations between Cr concentration in tree ring layers and tree ring width for P. occidentalis, and Ni and Cu for G. biloba. Also there were no significant correlations between climatic factors in Seoul and tree ring width.

A Study on the Adsorption of Heavy Metals by Chitosan Obtained from Shrimp Shell (새우껍질로부터 얻어진 키토산을 이용한 중금속 흡착에 관한 연구)

  • Cha, Wool-Suk;Kim, Jong-Soo;Cho, Bae-Sick;Kim, Chong-Kyun
    • Applied Chemistry for Engineering
    • /
    • v.9 no.4
    • /
    • pp.504-508
    • /
    • 1998
  • Experimental investigation on the adsorption of heavy metal confounds as $Fe^{2+}$, $Cu^{2+}$, $Mn^{2+}$, $Zn^{2+}$, $Ni^{2+}$, $Pb^{2+}$, $Cd^{2+}$, $Cr^{6+}$ using chitosan was carried out. The adsorption of each component of heavy metal compounds was measured by Atomic Absorption apparatus. The range of optimum pH for the removal rates of heavy metal compounds was found pH 7.0~9.0. The maximum time for the removal rate of $Fe^{2+}$ was observed about 15 min. The maximum time for the removal raters of $Cu^{2+}$, $Mn^{2+}$, $Zn^{2+}$, $Ni^{2+}$, $Pb^{2+}$, $Cd^{2+}$, and $Cr^{6+}$ was observed about 25 min. The adsorption rates of heavy metal compounds by chitosan have been found in the order of $Fe^{2+}>Cu^{2+}>Mn^{2+}>Zn^{2+}>Ni^{2+}>Pb^{2+}>Cd^{2+}>Cr^{6+}$.

  • PDF

Oral Bioavailability for Sub-micron Particle Curcumin (TheracurminCR-033P) and Absorption Rate by Product Composition in Healthy Human Volunteers (서브마이크론 입자 형태 커큐민의 생체 흡수율 및 제품 조성에 따른 흡수율 동등성 연구)

  • Park, Hee Jung;Takahashi, Tsukasa;Ozawa, Hitomi
    • Food Engineering Progress
    • /
    • v.21 no.3
    • /
    • pp.273-279
    • /
    • 2017
  • Curcumin have various health-beneficial properties in numerous studies. However, its bioavailability is low due to its limited intestinal uptake and rapid metabolism. This study aimed to evaluate the pharmacokinetics of newly developed sub-micron particle curcumin with increased water dispersibility (Theracurmin(R) CR-033P). Plasma curcumin levels were measured at 0, 1, 2, 4, 8 h after Theracurmin(R) CR-033P intake using high-performance liquid chromatography. For analyzing pharmacokinetics of Theracurmin(R) CR-033P, eighteen healthy subjects were recruited and received Theracurmin(R) CR-033P at a single oral dose containing curcumin 30 mg. $C_{max}$ was 28.14 ng/ml, and the area under the curve for 8 h was estimated to be 104.36 ng/ml. Based on the area under the plasma concentration (AUC), the bioavailability of sub-micron particle curcumin was higher 22-, 35-, 28-fold than native curcumin in men, women, and all subjects, respectively. For comparing by formulation, seven healthy subjects were recruited and received two type of treatment: (1) existing dosage form 300 mg (contained curcumin 30 mg) ${\times}$ 3 capsule, (2) high dosage form 300 mg (contained curcumin 90 mg) ${\times}$ 1 capsule + placebo 300 mg ${\times}$ 2 capsule. In the cross-over study, there was no significant differences in $C_{max}$ and AUC of plasma curcumin. In conclusion, submicron particle curcumin with increased water dispersibility significantly improved its oral bioavailability and women absorbed curcumin more effectively than men. Different formulation of Theracurmin(R) CR-033P has shown equivalent to the reference in terms of pharmacokinetics.

Worker Exposure Assessment on Airborne Total Chromium and Hexavalent Chromium by Process in Electroplating Factories (도금업체 공정별 근로자의 총크롬 및 6가 크롬 노출 평가)

  • Yi, Gwang Yong;Kim, Boowook;Shin, Yong Chul
    • Journal of Korean Society of Occupational and Environmental Hygiene
    • /
    • v.25 no.1
    • /
    • pp.89-94
    • /
    • 2015
  • Objectives: The objective of this study was to determine characteristics of workers' exposures to airborne total and hexavalent chromium by job title in electroplating processes. Methods: Total Cr was determined through a modified method based on NIOSH Method 7024. Airborne hexavalent Cr, Cr(VI), was sampled and extracted according to NIOSH Method 7600 and analyzed at 520 nm using an ion chromatograph/visible detector. Results: The geometric mean(GM) of total Cr concentrations from all factories was $11.2{\mu}g/m^3$(GSD=4.9). The GM of Cr(VI) concentrations from all factories was $2.84{\mu}g/m$ (GSD=5.2), and the concentrations among factories were significantly different (p<0.05). The Cr(VI) levels were lower than total Cr levels. Total Cr exposure levels were highest among buffing workers ($21.6{\mu}g/m^3$), but Cr(VI) levels were highest among plating workers($4.15{\mu}g/m^3$). The concentrations of Cr(VI) and total Cr from plating tasks was highly correlated(r=0.91). Conclusions: In the electroplating industry, plating workers were mainly exposed to Cr(VI), but others were not. Oxidation-reduction states of Cr and job titles should be considered in the exposure or risk assessments of chrome electroplating factories.

The Characteristics of Adsorption Treatment of Cr(VI)-containing Wastewater using Kudzu as the Adsorbent (칡을 이용(利用)한 크롬페수(廢水) 흡착(吸着) 처리(處理) 특성(特性))

  • Seo, Myung-Soon;Kim, Dong-Su
    • Resources Recycling
    • /
    • v.17 no.3
    • /
    • pp.56-61
    • /
    • 2008
  • The kudzu has been investigated as an adsorbent for treatment of Cr(VI)-containing wastewater. The specific surface of kudzu was analyzed to be $189.91m^2/g$ and its major composition were found to be nitrogen and oxygen. It was observed that adsorption reaction for Cr(VI) on kudzu meets 1st order in kinetics and Langmuir Model in equilibrium. As the pH of wastewater was increased, the adsorbed amount of Cr(VI) onto kudzu was increased due to the pre-combination of $OH^-$ with adsorbent and the efficiency of adsorption was found to be 60% when real electroplating Cr(VI)-containing wastewater was applied.

Bioaccumulation of Chromium Ions by Immobilized Cells of a Filamentous Cyanobacterium, Anabaena variabilis

  • Khattar, Jasvir I.S.;Sarma, Tangirala-A.;Singh, Davinder-P.;Sharma, Anuradha
    • Journal of Microbiology and Biotechnology
    • /
    • v.12 no.1
    • /
    • pp.137-141
    • /
    • 2002
  • Anabaena variabilis ATCC 29413 grew in chromium (Cr) containing Chu-10 (basal) and nitrate-supplemented media, and the growth of the organism in $100{\mu}M$ chromium was found to be 50% of that in control medium. The growth in nitrate $({NO_3}^-)$ supplemented cultures was better as compared to cultures grown in basal medium. Free cells from basal and nitrate-supplemented media removed 5.2 and 7.4 nmol of chromium $mg^{-1}$protein in 8 h, respectively, from the medium containing $30{\mu}M$ chromium. The efficiency of chromium removal increased 7-fold in imidazole buffer (0.2 M, pH 7.0). A cell density equivalent to $100{\mu}g$ protein $ml^{-1}$ was found to be optimum for maximum Cr removal. Entrapment of cells in calcium-alginate beads did not affect the rate of Cr uptake by the cells. The efficiency of the laboratory-scale continuous flow bioreactor $(12.5{\times}2cm)$ loaded with alginate-immobilized cells (10 mg protein) and fed with $30{\mu}M$ chromium solution was compared at different flow rates. The efficiency of the bioreactor varied with flow rates. In terms of percent removal of Cr from influent, a flow rate of 0.1 ml $min^{-1}$ was found to be optimum for 6 h (54% Cr removal efficiency). Maximum amount of Cr (883 nmol) was removed by the cells in 3 h at a flow rate of 0.5 ml $min^{-1}$. The potential use of A. variabilis in removing Cr from industrial effluents is discussed.

SCANNING ELECTRON MICROSCOPIC STUDY OF IMPLANT SURFACE AFTER Er,Cr:YSGG LASER IRRADIATION (Er,Cr:YSGG 레이저를 조사한 임플란트 표면의 주사전자현미경적 연구)

  • Jo, Pil-Kwy;Min, Seung-Ki;Kwon, Kyung-Hwan;Kim, Young-Jo
    • Maxillofacial Plastic and Reconstructive Surgery
    • /
    • v.28 no.5
    • /
    • pp.454-469
    • /
    • 2006
  • Today, there is considerable evidence to support a cause-effect relationship between microbial colonization and the pathogenesis of implant failures. The presence of bacteria on implant surfaces may result in an inflammation of the peri-implant mucosa, and, if left untreated, it may lead to a progressive destruction of alveolar bone supporting the implant, which has been named as peri-impantitis. Several maintenance regimens and treatment strategies for failing implants have been suggested. Recently, in addition to these conventional tools, the use of different laser systems has also been proposed for treatment of peri-implant infections. As lasers can perform excellent tissue ablation with high bactericidal and detoxification effects, they are expected to be one of the most promising new technical modalities for treatment of failing implants. It is introduced that Er,Cr:YSGG laser, operating at 2780nm, ablates tissue by a hydrokinetic process that prevents temperature rise. We studied the change of the titanium implant surface under scanning electron microscopy after using Er,Cr:YSGG laser at various energies, irradiation time. In this study, Er,Cr:YSGG laser irradiation of implant fixture showed different effects according to implant surface. Er,Cr:YSGG laser in TPS surface with RBM not alter the implant surface under power setting of 4 Watt(W) and irradiation time of 30sec. But in TPS surface with $Ca_3P$ coating alter above power setting of 2W and irradiation time of 10sec. TPS surface with RBM showed microfracture in 4W, 30sec and TPS surface with $Ca_3P$ coating showed destruction of fine crystalline structure, melting in excess of 2W, 10sec. We concluded that proper power setting, air, water of each implant surface must be investigated and implant surface must be irradiated under the damaged extent.

Association between Bone Mineral Density and Bone Nutrition Indicators in Elderly Residing in Low Income Area of the City (도시거주 저소득층 노인들의 골지표 및 영양소섭취와 골밀도와의 상관관계에 관한 연구)

  • 손숙미;전예나
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.33 no.1
    • /
    • pp.107-113
    • /
    • 2004
  • This study explored the association between the bone nutrition indicators and the bone mineral density (BMD) in 138 apparently healthy elderly (male: 38, female: 100) dwelling in a low income area of the city. Dietary intakes were estimated from two meals (breakfast & dinner) and snack using 24 hr-recall method and lunch with weighing over 3 consecutive days. Female elderly showed significant lower intakes (p<0.001∼p<0-05) for most of the nutrients except calcium and vitamin C than the elderly male. Calcium and vitamin D intakes for both male and female were 331.0 mg, 1.89 $\mu\textrm{g}$ and 308.6 mg, 1.21 $\mu\textrm{g}$, respectively and they were below the 50% of the RDA. Both the BMDs at lumbar spine (LS) and femoral neck (FN) were positively correlated with the energy intake, calcium intake and vitamin D intake (p<0.05, respectively) for male. In female BMDs of the both sites were positively correlated with the intakes of carbohydrates, protein, lipid, calcium and vitamin D (p<0.01∼p<0.05). Female showed higher serum osteocalcin (p<0.01) and urinary deoxypyridinoline/creatinine (DPYR/CR) (p<0.001), meaning that female had elevated rate in bone turn over and bone resorption. The proportion of subjects with vitamin D deficiency assessed with serum 25(OH)VitD$_3$<10 mg/mL was 35.0% for female and 23.7% for male, respectively Both the BMDs at lumbar spine and trochanter were positively correlated with serum 25(OH)VitD$_3$ but BMDs in most of the sites were negatively associated with urinary DPYR/CR, phosphate/CR. Stepwise multiple regression showed physical activity, serum alkaline phosphatase, weight, vitamin D explained 47.6% of the variation of the LS BMD. The indicator variable for serum alkaline phosphatase was negatively associated with LS BMD. However, the indicator variable for weight and vitamin D intake were positive and significant (p=0.0087, p=0.0007, respectively). For FN BMD, the indicator variable for age and serum alkaline phosphatase were negative and significant (p<0.0075, p<0.0015, respectively) and the weight was positively associated with the FN BMD.

PSNR Correlation between CR and DR according to Changed KvP (CR과 DR의 kVp 변화에 따른 PSNR 상관관계)

  • Kim, Jisun;Ahn, Byungju
    • Journal of the Korean Society of Radiology
    • /
    • v.8 no.7
    • /
    • pp.417-422
    • /
    • 2014
  • In this study, the influence degree of the scattering of the line depending on the incident energy of the radiation objective was to evaluate a new method of quantitative methods of PSNR is provided.Value of MSE and PSNR of the DR and the Target is placed at the left when there was no change in CR Target, the change appeared to ttaran MSE and PSNR value in tube voltage. Both CR and DR seen that there is a variation of the MSE and PSNR depending on the tube voltage change Computon showed that the scattered radiation effects. If the CR and DR 80 The changes in the MSE and PSNR experience the symptoms suddenly occur in areas kVp was found to affect the optoelectronic Computon E, and at the same time, the scattered radiation detector Computon Computon by scattering due to the photoelectric effect. CR and DR of the imaging device in the future on the basis of the energy bands of the photoelectric effect of 60 kVp 70 kVp, 80 kVp, 90 kVp, compares the value of the PSNR and MSE 100 kVp in accordance with the change of the tube voltage of the CR and device DR proposes jigil scattering study of the degradation of the line quality is achieved.