• Journal of Preventive Medicine and Public Health
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• v.28 no.4 s.51
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• pp.863-873
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• 1995

This report describes a preperation and characterization of canine blood lead(Pb) standard reference material(SRM). Three adult beagle dogs(A, B, and C)were orally dosed with gelatin capsules containing $Pb(NO_3)_2$, equivalent to $10\sim80mg$ Pb/kg body weight. Blood was drawn 24 hours after the dose from the cephalic vein into lead free 500ml Pyrex beaker in which EDTA.K was contained as an anticoagulant. The amount of lead given to individual dog was varied arbitrarily. Three month later, 3 canine animals were orally dosed with lead secondarily to make mixed SRM(D1) which was mixed different concentrations of lead in bloods with A1, B1, and C1 in vitro. The SRMs for A, B, C, A1, B1, C1, and D1 were distributed 2ml each into more than 300 lead free bottles, and were stored in refregerator at $4^{\circ}C$. The amount of lead in canine whole blood samples were determined using a Varian 30A atomic absorption spectrophotometer(AAS) with a model GTA-96 graphite tube atomizer with D2 background correction and a Hitachi Z-8100 AAS with Zeeman background correction. The sensitivity and detection limits for lead determination of Varian 30A were $0.46{\mu}g/L,\;0.34{\mu}g/L,\;and\;0.56{\mu}g/L,\;0.14{\mu}g/L$ of Hitachi Z-8100, respectively. Day to day variations in determination of blood lead concentration in a certain sample were $31.11{\pm}1.36{\mu}g/100ml$ by Varian 30A, and $33.08{\pm}0.82{\mu}g/100ml$ by Hitachi Z-8100, showing the difference of 3% between the two results. At the blood lead concentrations of $56.31{\pm}1.98{\mu}g/100ml(A),\;40.89{\pm}0.80{\mu}g/100ml(B),\;59.01{\pm}1.38{\mu}g/100ml(C)$, the precisions of replicated measurements by AAS were 3.52%, 1.96%, and 2.34%, respectively. Coefficient variation(CV) of SRMs(A, B, and C) within a standard sample were ranged from 0.92% to 7.50%, and those between 5 standard samples were 1.21%, 2.64%, and 1.11%, respectively, showing inter-vial variation of $1{\mu}g/100ml$. Lead levels in SRMs during one month storage were unchanged. The overall recoveries were $89.6\sim100.4%,\;91.6\sim101.9%,\;90.3\sim100.0%$ for A, B, and C SRMs, means were $56.46{\pm}2.69{\mu}g/100ml,\;39.35{\pm}1.89{\mu}g/100ml,\;57.40{\pm}2.31{\mu}g/100ml$, and measurement ranges were$52.88{\pm}59.26{\mu}g/100ml,\;37.47{\pm}41.68{\mu}g/100ml,\;54.80{\pm}60.69{\mu}g/100ml$, respectively. Those results were laid within confidence limits values. The lead concentrations in the mixed sample(D1) stored over one month period were ranged from $32.76{\mu}g/100ml\;to\;33.54{\mu}g/100ml$, with CV ranging from 1.2% to 2.7%. The results were similiar to each of single samples(A1, B1, and C1) in respect of homogeneity and stability. Results of the mixed blood sample analysed after 1 month storage at $4^{\circ}C$ by four other laboratories(L1, L2, L3, L4) were similar with those of our laboratory($L5;31.18{\pm}0.24{\mu}g/100ml$, acceptable range by $CDC;25.18\sim37.18{\mu}g/100ml$), showing the concentrations of $25.91{\pm}1.19{\mu}g/100ml(L1),\;34.16{\pm}0.22{\mu}g/100ml(L2),\;35.68{\pm}0.85{\mu}g/100ml(L3),\;30.95{\pm}0.46{\mu}g/100ml(L4)$ in a each samples.

• The Korean Journal of Nuclear Medicine
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• v.39 no.3
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• pp.200-208
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• 2005

Purpose: Tc-99m labeled diethylenetriaminepentaacctic acid (DTPA)-coupled galactosylated human serum albumin (GSA) is a currently used imaging agent for asialoglycoprotein receptor (ASGPR) of the liver, but, it has several shortcomings. Recently a new ASGPR imaging agent, $^{99m}Tc$-lactosylated human serum albumin (LSA), with simple labeling procedure, high labeling efficiency, high stability was developed. In order to assess the feasibility of the $^{99m}Tc$-LSA as a ASGPR imaging radiopharmaceuticals, we performed biodistribution study of the tracer in liver injured mice model and the results were compared with histolgic data. Materals and Methods: To induce hepatic damage in ICR mice, diethylnitrosamine (DEN) ($60mg/kg/week{\times}5time$, low dose or $180mg/kg/week{\times}2times$, high dose) and thioacetamide (TAA) ($50mg/kg{\times}1time$) were administrated intraperitoneally. Degree of liver damage was evaluated by tissue hematoxilin-eosin stain, and expression of asialoglycoprotein receptor (ASGPR) was assessed by immunohistochemistry using ASGPR antibody. $^{99m}Tc$-LSA was intravenously administrated via tail vein in DEN or TAA treated mice, and biodistribution study of the tracer was also performed. Results: DEN treated mice showed ballooning of hepatocyte and inflammatory cell infiltration in low dose group and severe hapatocyte necrosis in high dose group, and low dose group showed higher ASGPR staining than control mice in immunohistochemical staining. TAA treated mice showed severe hepatic necrosis. $^{99m}Tc$-LSA Biodistribution study showed that mice with hepatic necrosis induced by high dose DEN or TAA revealed higher blood activity and lower liver activity than control mice, due to slow clearance of the tracer by the liver. The degree of liver uptake was inversely correlated with the degree of histologic liver damage. But low dose DEN treated mice with mild hepatic injury showed normal blood clearance and hepatic activity, partly due to overexpression of ASGPR in mice with mild degree hepatic injury. Conclusion: Liver uptake of $^{99m}Tc$-LSA was inversely correlated with degree of histologic hepatic injury in DEN and TAA treated mice. These results support that $^{99m}Tc$-LSA can be used to evaluate the liver status in liver disease patients.

• Applied Chemistry for Engineering
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• v.31 no.2
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• pp.115-124
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• 2020

Sustainable plastics can be mainly categorized into (1) biodegradable plastics decomposed into water and carbon dioxide after use, and (2) biomass-derived plastics possessing the carbon neutrality by utilizing raw materials converted from atmospheric carbon dioxide to biomass. Recently, biomass-derived engineering plastics (EP) and natural nanofiber-reinforced nanocomposites are emerging as a new direction of the industry. In addition to the eco-friendliness of natural resources, these materials are competitive over petroleum-based plastics in the high value-added plastics market. Polyesters and polycarbonates synthesized from isosorbide and 2,5-furandicarboxylic acid, which are representative biomass-derived monomers, are at the forefront of industrialization due to their higher transparency, mechanical properties, thermal stability, and gas barrier properties. Moreover, isosorbide has potential to be applied to super EP material with continuous service temperature over 150 ℃. In situ polymerization utilizing surface hydrophilicity and multi-functionality of natural nanofibers such as nanocellulose and nanochitin achieves remarkable improvements of mechanical properties with the minimal dose of nanofillers. Biomass-derived tough-plastics covered in this review are expected to replace petroleum-based plastics by satisfying the carbon neutrality required by the environment, the high functionality by the consumer, and the accessibility by the industry.

• Journal of Animal Environmental Science
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• v.9 no.1
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• pp.9-18
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• 2003

Most of broiler houses in Korea have the trouble of environmental control such as suitability, stability, and uniformity of internal climate, resulting in serious stress on chickens. Accordingly, it is very urgent to develop optimum designs of naturally and mechanically ventilated broiler houses for Korean climate. In this study, the internal climates such as air temperature, humidity, dust, ammonia gas, and air velocity were measured at a naturally ventilated broiler house. The data were collected during summer season including local weather data. It was found that the difference between measured and optimum air temperatures was $14.0^{\circ}C$ in maximum during the summer time. The daily maximum range of internal averaged air temperature was found $10.5^{\circ}C$ while the uniformity was $5.2^{\circ}C$ in maximum. The maximum, average, and minimum internal averaged relative humidity were 89.3%, 73.7%, and 49.2%, respectively while locally measured were 95.1% and 47.2%, respectively in maximum and minimum. Considering Temperature-humidity index, during summer season, over 97% of totally rearing period was shown that counter plan is needed for thermal stress while it was very dangerous situation for 22% of the rearing period. The ammonia gas and dust concentrations were seriously affected by the broilers activity, growth level, and relative humidity.

• Journal of Animal Environmental Science
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• v.18 no.2
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• pp.111-122
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• 2012

Establishment of the LFQC (Liquid Fertilizer Quality Certification) system is very urgent issue for recycling livestock manure as renewable resources in Korea faced with environmental problem of manure application to land due to intensive livestock farming. In this study, we investigated relevant laws and regulations on livestock manure fertilizer, certifications of eco-friendly agricultural products, government policies on livestock manure management to establish reasonable direction of Korean LFQC (Liquid Fertilizer Quality Certification) system. As a result from this study, the liquid fertilizers in 'LFQC' system could be classified as three levels according to the usage patterns in field; 1st. Individual Farm Level (IFL), 2nd. Joint Farm Level (JFL), and 3rd. Commercial Level (CML). And finally, we found some characteristics in 'Main Level-Grading Factors' of liquid fertilizer such as fertilizing value, harmfulness, stability, uniformity, economic effect, storage potential, commercial value, functionality. Those items were considered to be the key factors for the establishment of 'LFQC' system. More research on 'Evaluation Standards' for concrete guideline and on the 'Main Level-Grading Factors' be needed to complete Korean LFQC system.

• Korean Journal of Food Science and Technology
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• v.45 no.1
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• pp.59-69
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• 2013

This study investigated the frequency, amount and consumption patterns of 50 potentially hazardous foods (PHF) along with consumers' risk perceptions towards PHF in Korea. A quantitative survey was performed from May through August by trained interviewers, surveying 1,000 adults aged over 18 who were randomly selected from six major provinces in Korea. Consumers perceived seafood, including shellfish, mussel, sashimi and sushi, as the top foods with the highest risk, followed by raw sliced beef. The food with the highest frequency intake per month was leafy vegetables, which is used to wrap other foods, followed by blanched vegetables, fried chicken, etc. The group of middle aged individuals with economic stability had the highest frequency intake of sashimi and sushi. Respondents living in small regions consume greater PHF portions at once. Food safety education with regard to the risk of PHF is essential for consumers, with high frequent intake of PHF.

• The Korean Journal of Food And Nutrition
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• v.18 no.4
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• pp.341-348
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• 2005

The quality characteristics of bread added with the levels of $0\%,\;1.0\%,\;2.0\%\;3.0\%\;and\;4.0\%$ prickly pear powder were investigated. Mixing water absorption capacity was increased by increasing amounts of prickly pear powder. Mixing time of dough was increased compared to that of wheat flour by added prickly pear powder, while it decreased as prickly pear powder content increased. Dough stability of wheat flour added with $1.0\%$ prickly pear powder was similar to wheat flour dough, while decreased by increasing amount of prickly pear powder at the range of $2.0\~4.0\%$. Pasting temperature($66.1\~66.9^{\circ}C$) of wheat flour added with $1.0\%,\;2.0\%\;3.0\%\;and\;4.0\%$ prickly pear powder was lower($67.8^{\circ}C$) than that of wheat flour. Peak viscosity($2,226\~2,375$ cp) of wheat flour added with $1.0\%,\;2.0\%\;3.0\%\;and\;4.0\%$ prickly pear powder were higher(2,288 cp) than control, and increased with increasing amount of prickly pear powder Setback($797\~750$ cp) of wheat flour added with $1.0\%,\;2.0\%\;3.0\%\;and\;4.0\%$ prickly pear powder were lower(803 cp) than that of wheat flour, and decreased with increasing amount of prickly pear powder. The volume of dough added with prickly pear powder decreased compared to that of the wheat dough. The specific loaf volume of bread added with prickly pear powder decreased($8.0\~18.5\%$) compared to that of the wheat bread. Color of crumb was deep red gradually with the increasing amount of substituted prickly pear powder. Hardness, adhesiveness, gumminess and chewiness of bread were increased gradually with the increasing amount of substituted prickly pear powder but the springiness was decreased. The sensory evaluation showed that bread of wheat flour added with $2.0\%$ prickly pew powder was superiority than the wheat flour bread.

• Food Science of Animal Resources
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• v.30 no.3
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• pp.472-478
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• 2010

The effects of rosemary and $\alpha$-tocopherol, added individually or in combination, on broiler performance, thiobarbituric acid reactive substance (TBARS), total plate count (TPC) and meat color of chicken thigh meat were investigated. Three hundred broiler chicks divided into five groups were fed a basal diet (control) or basal diet supplemented with 5 g rosemary/kg (T1), 10 g rosemary/kg (T2), 200 mg $\alpha$-tocopherol/kg (T3), or 5 g rosemary/kg + 200 mg $\alpha$-tocopherol/kg (T4) for 5 weeks. Following slaughter, chicken meat was stored at $4^{\circ}C$ for 10 days. All treatments did not influence the performance. Rosemary supplementation delayed lipid oxidation in thigh meat during refrigerated storage. T2 was significantly (p<0.05) more effective in delayed lipid oxidation compared to T1, but was inferior to T3. Samples containing a combination of antioxidant had lower TBARS values than those containing the individual antioxidants, indicating a synergistic effect. TPC was significantly increased (p<0.05) in thigh meat of all groups throughout the refrigerated storage. The T3 and control groups showed TPC counts that did not differ from each other during the entire storage period. However, rosemary supplementation was associated with bacterial counts that were significantly lower (p<0.05) than the control and $\alpha$-tocopherol groups at day 3 of storage and thereafter. For this period, T1 presented TPC counts that were significantly higher than the T2 group (p<0.05). At all storage times, the thigh meat of rosemary-fed chickens was redder than control (higher $a^*$), while no differences in $L^*$ and $b^*$ values were found. A synergistic effect was obtained from the combination of rosemary with $\alpha$-tocopherol, whereas individual use of the antioxidants significantly improved color stability compared to the control.

• Korean Journal of Food Science and Technology
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• v.34 no.6
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• pp.1140-1144
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• 2002

Molecular relaxation behaviors of crystalline glucose anhydrous, crystalline glucose monohydrate, and amorphous glucose with different particle sizes were observed by measuring spin-spin relaxation time constant $(T_2)$ at the temperature range of $-20\;to\;110^{\circ}C$ using temperature-controlled low field nuclear magnetic resonance spectroscopy. No change in $T_2$ values of crystalline glucose anhydrous was observed throughout the temperature range, whereas $T_2$ values of crystalline glucose monohydrate and amorphous glucose increased from around $45\;and\;65^{\circ}C$, respectively. These results indicate that molecular mobility of crystalline glucose anhydrous does not change even at temperature higher than $100^{\circ}C$ and that the stability of powdered glucose could be improved by increasing the particle size of materials.

• Korean Journal of Food Science and Technology
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• v.34 no.6
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• pp.1048-1056
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• 2002

Quality of fresh ginger deteriorates rapidly during low temperature storage, and its storage life is short due to sprouting and microbial spoilage. The objectives of this research were to develop, using additives, a minced ginger product, which could maintain acceptable quality for over 30 days, and to investigate its quality changes during the cold storage. Storage stability of minced ginger product was investigated from the standpoint of the inhibition of brown discoloration, gas formation and liquid-solid separation. Fresh ginger was peeled and ground to produce minced ginger (control). Sodium bisulfite, L-cysteine, NaCl, sodium benzoate, modified starch, and/or xanthan gum were added to the control to minimize quality loss during storage, and to develop an optimum formula (A) of minced ginger. Samples were packed in Nylon/PE films, stored at $5^{\circ}C$, sampled at a 30-day interval, and subjected to quality evaluations. Changes in pH, surface color, gas formation, liquid-solid separation, contents of free amino acids, free sugars, organic acids, and fatty acids were determined. Gas formation was effectively inhibited in samples with sodium benzoate and/or NaCl. Samples with xanthan gum did not result in liquid-solid separation. L-Cysteine and sodium bisulfite were effective in controlling discoloration. pH decreased during storage in all samples, except sample A. Organic acid contents of all samples increased during storage, with lactic acid content showing the highest increase. Free amino acid content decreased with increasing storage time. Free sugar content of all samples decreased during storage. Sensory results showed sample A maintained acceptable quality until 90 days of storage. These results suggest that quality of minced ginger could be successfully maintained with the additions of selected additives for up to 90 days.