• Food Science of Animal Resources
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• v.40 no.6
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• pp.969-979
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• 2020

Fresh grass carp was used to produce surimi and 50 g/kg, 100 g/kg, or 150 g/kg pork back fat was added. The water distribution, thiobarbituric acid reactive substances (TBARS), myoglobin oxidation, color parameter (L*, a*, and b*), heme and non-heme iron content of samples were determined to analyze the effects of different fat content on the oxidation of myoglobin and lipids during multiple freeze-thaw cycles of grass carp surimi. Both multiple freeze-thaw cycles and increased fat content lead to an increase in TBARS, a blue shift in the absorption peak of myoglobin porphyrin, a decrease in heme iron content, and an increase of non-heme iron content. Repeated freeze-thaw caused a decrease in immobilised water content and L*, and caused an increase in a* and b*. Increased fat content caused an increase in immobilised water content, L* and a*, and caused a decrease in b*.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.05a
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• pp.181-182
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• 2016

We developed eco-friendly lightweight concrete in order to apply eco-friendly lightweight concrete into structural wall or slab of shallow depth urban railway system. However, since lightweight aggregate has different structural feature of porous and it has been overvalued at current KS standard when applied, we did compare the characteristics of freezing and thawing of normal weight aggregate concrete by comparative test method(KS, ASTM). According to test method, there was a big difference of dynamic elastic modulus in lightweight concrete rather than in normal weight aggregate concrete. The big absorption factor in lightweight aggregate is main reason for that. For more detail, in KS law in which only 14 days water curing is carried out, the big amount of moisture in lightweight aggregate is frozen and high heaving pressure occurs and finally that lead to destruction of lightweight concrete. Therefore, it is considered that in case of lightweight concrete, resistibility against freezing and thawing has been undervalued in domestic KS law compared to ASTM law, which is overseas standard. So, a variety of examination about testing criteria and rule would be necessary for exact assessment of lightweight concrete.

• The Journal of Korean Society for Radiation Therapy
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• v.7 no.1
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• pp.15-31
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• 1995

The radiosurgery treatment is one time, non surgical approach to the treatment of patients with intracranial disorders whose conditions would be difficult or dangerous to treat with conventional sugical procedures. The LINAC based radiosurgery is based on the combination of multiple isocentric arc irradiation with small fields centered in the stereotactic target. The absorption of the beam in a tissue equivalent medium, such as water, as well as the uniformity, or profile, of the beam must be precisely documented. The beam characteristics and dosimetric measurememts of the 6MV X-ray beam from a ML-6M linear accelerator are examined. The percent depth dose (PDD) and beam profile (including flatness, symmetry and penumbra) is calibrated with the radiosurgery cone in water phantom. The cone is made of lead which size is from $10{\times}10mm{\phi}$ to $30{\times}30mm{\phi}$ All of these dosimetric measurements sufficiently characterized the beam to permit safe clinical use.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.34 no.6
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• pp.466-472
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• 2012

The loss of mandibular continuity due to trauma, neoplasm, or infection results in major esthetic and biologic compromise. The reconstruction of the mandibular bone defect still poses a challenge to oral and maxillofacial surgeons. There have been a number of variety graft materials. Among them, free block bone graft with rigid fixation has been widely used. However, cases using free block bone grafts may lead to a marked invasion of the donor site, mal-union, and absorption of the block bone. In this respect, particulate cortical bone using a titanium mesh tray can be an effective alternative option in order to achieve a proper bone contour and good oral rehabilitation. We have developed an intraoral approach for the mandibular reconstruction method using a titanium mesh tray with autogenous particulate cortical bone graft.

• Journal of the East Asian Society of Dietary Life
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• v.22 no.2
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• pp.278-289
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• 2012

This study investigated the quality characteristics of $Jajang$ noodles with added spinach (20%, 30% and 50% based on water). Significant increases ($p$<0.05) were found in cooked weight, water absorption of cooked noodles, turbidity of soup, while soup volume did not changed in proportion to the addition of spinach. Decrease of L and a values and an increase of b values were shown with the increase of spinach concentration. For textural properties, hardness was the lowest in 50% spinach noodles and the highest in 20% spinach noodles. The cohesiveness and springiness values of 20% and 30% spinach noodles were superior to those of the control, but a rise in spinach concentration (50%) lead to a reduction these values. In a sensory evaluation, the most acceptable sample was the 30% spinach noodle sample. These results suggest an addition of 30% spinach is suitable for spinach $Jajang$ noodle processing.

• Journal of the Korean Chemical Society
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• v.57 no.3
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• pp.316-321
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• 2013

Electrocoagulation (EC) technique is applied for the treatment of wastewater containing heavy metals ions such as nickle (Ni), lead (Pb) and cadmium (Cd) by using sacrificial anodes corrode to release active coagulant flocs usually aluminium or iron cations into the solution. During electrolytic reactions hydrogen gas evolve at the cathode. All the experiments were carried out in Batch mode. The tank was filled with synthetic wastewater containing heavy metals and efficiency of electro-coagulation in combination with aluminum and iron electrodes were investigated for removal of such metals. Several parameters, such as contact time, pH, electro-coagulant concentration, and current density were optimized to achieve maximum removal efficiency (%). The concentrations of heavy metals were determined by using Atomic Absorption Spectroscopy (AAS). It is found that the electro-coagulation process has potential to be utilized for the cost-effective removal of heavy metals from wastewater specially using iron electrodes in terms of high removal efficiencies and operating cost.

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2004.05a
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• pp.27-29
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• 2004

Drug transporters play an essential role in the absorption, distribution and elimination of clinical drugs, nutrients and toxicants. The importance of the transporters is exampled by therapeutic failure in cancer chemotherapy that is mainly caused by the overexpression of multidrug resistance (MDR)-related transporters. In addition, the transporters may involve in drug-drug interactions that lead to serious adverse drug responses and some transporters also contribute to inter-individual variation in drug responses. As an effort to understand the mechanism underlying the inter-individual variation of transporters activity, genetic and environmental factors influencing the expression or function of the transporters have extensively explored through last decade. Among them, genetic polymorphism of drug transporter encoding genes has generated much interest since the discovery of functional single nucleotide polymorphisms (SNP) of MDR1 gene. Besides drug transporters, xenobiotic receptors also modulate drug disposition by regulating the transcription of drug metabolizing enzymes and drug transporters. Among many xenobiotic receptors, pregnane X receptor (PXR) and constitutive androstane receptor (CAR) are two most well characterized since these receptors show wide substrate specificities and regulate the expression of various enzymes involved in drug disposition. Recently, several functional genetic polymorphisms were reported in PXR coding gene. In the present study, genetic polymorphisms of two drug transporters, MDR1 and BCRP, and two xenobiotic receptors, PXR and CAR, were investigated in Korean population.

• Proceedings of the Korean Society of Toxicology Conference
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• 2004.05a
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• pp.27-29
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• 2004

Drug transporters play an essential role in the absorption, distribution and elimination of clinical drugs, nutrients and toxicants. The importance of the transporters is exampled by therapeutic failure in cancer chemotherapy that is mainly caused by the overexpression of multidrug resistance (MDR)-related transporters. In addition, the transporters may involve in drug-drug interactions that lead to serious adverse drug responses and some transporters also contribute to inter-individual variation in drug responses. As an effort to understand the mechanism underlying the inter-individual variation of transporters activity, genetic and environmental factors influencing the expression or function of the transporters have extensively explored through last decade. Among them, genetic polymorphism of drug transporter encoding genes has generated much interest since the discovery of functional single nucleotide polymorphisms (SNP) of MDRl gene. Besides drug transporters, xenobiotic receptors also modulate drug disposition by regulating the transcription of drug metabolizing enzymes and drug transporters. Among many xenobiotic receptors, pregnane X receptor (PXR) and constitutive androstane receptor (CAR) are two most well characterized since these receptors show wide substrate specificities and regulate the expression of various enzymes involved in drug disposition. Recently, several functional genetic polymorphisms were reported in PXR coding gene. In the present study, genetic polymorph isms of two drug transporters, MDR1 and BCRP, and two xenobiotic receptors, PXR and CAR, were investigated in Korean population.

• Journal of Nutrition and Health
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• v.32 no.2
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• pp.175-181
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• 1999

The prevalence of alcoholism among elderly population is reported to be high in rural areas in Korea. Chronic abuse of alcohol can lead to the development of vitamin B deficiency through inadequate intake, altered absorption and metabolism, and increased excretion. The present study was conducted to assess vitamin B1 and B2 status in seventeen alcohol dependent subjects who do not exhibit any clinical neurological symptoms. Vitamin B1 and B2 nutritional states were determined enzymatically by measurement of transketolase and glutathione reductase activities in erythrocytes, respectively. And dietary intakes of nutrients were determined by a 24-hr recall method. The mean percent activation of erythrocyte transketolase was significantly higher in alcoholics than in alcoholics than in control (p<0.05). The proportion of subjects with a low and borderline status of vitamin B1, was significantly higher in alcoholics than in control (p<0.05). The mean percent activation of erythrocyte glutathione reductase was not different between alcoholics and control. And the proportion of subjects with low and borderline status of Vitamin B2, was higher in alcoholics than in control (p<0.1). Vitamin B1 and B2 status were significantly decreased in alcoholics who were smoking cigarettes compared to non-smoking and non-alcoholic subjects(p<0.05). Whether vitamin supplementation improves the vitamin status of alcohol dependent subjects remains to be researched.

• Korean Journal of Materials Research
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• v.31 no.9
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• pp.496-501
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• 2021

Metal halide perovskite nanocrystals, due to their high absorption coefficient, high diffusion length, and photoluminescence quantum yield, have received significant attention in the fields of optoelectronic applications such as highly efficient photovoltaic cells and narrow-line-width light emitting diodes. Their energy band structure can be controlled via chemical exchange of the halide anion or monovalent cations in the perovskite nanocrystals. Recently, it has been demonstrated that chemical exfoliation of the halide perovskite crystal structure can be achieved by addition of organic ligands such as n-octylamine during the synthetic process. In this study, we systematically investigated the quantum confinement effect of methylammonium lead bromide (CH₃NH₃PbBr₃, MAPbBr₃) nanocrystals by precise control of the crystal thickness via chemical exfoliation using n-octylammonium bromide (OABr). We found that the crystalline thickness consistently decreases with increasing amounts of OABr, which has a larger ionic radius than that of CH₃NH₃⁺ ions. In particular, a significant quantum confinement effect is observed when the amounts of OABr are higher than 60 %, which exhibited a blue-shifted PL emission (~ 100 nm) as well as an increase of energy bandgap (~ 1.53 eV).