• Asian Pacific Journal of Cancer Prevention
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• v.15 no.8
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• pp.3651-3657
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• 2014

Hepatocellular carcinoma (HCC) has a relatively higher incidence in many countries of Asia. Globally, HCC has a high fatality rate and short survival. Epirubicin, a doxorubicin analogue, may be administered alone or in combination with other agents to treat primary liver cancer and metastatic diseases. However, the toxic effects of epirubicin to normal tissues and cells have been one of the major obstacles to successful cancer chemotherapy. Here, we investigated the effects of epirubicin in combination with kappa-selenocarrageenan on mice with H22 implanted tumors and HepG-2 cell proliferation, immune organ index, morphology, cell cycle and related protein expressions in vivo and in vitro with sequential drug exposure. The inhibitory rate of tumor growth in vivo was calculated. Drug sensitivity was measured by MTT assay, and the King's principle was used to evaluate the interaction of drug combination. Morphological changes were observed by fluorescent microscopy. Cell cycle changes were analyzed by flow cytometry. Expression of cyclin A, Cdc25A and Cdk2 were detected by Western blotting. In vivo results demonstrated that the inhibitory rate of EPI combined with KSC was higher than that of KSC or EPI alone, and the Q value indicated an additive effect. In addition, KSC could significantly raise the thymus and spleen indices of mice with H22 implanted tumors. In the drug sensitivity assay in vitro, exposure to KSC and EPI simultaneously was more effective than exposure sequentially in HepG-2 cells, while exposure to KSC prior to EPI was more effective than exposure to EPI prior to KSC. Q values showed an additive effect in the simultaneous group and antagonistic effects in the sequential groups. Morphological analysis showed similar results to the drug sensitivity assay. Cell cycle analysis revealed that exposure to KSC or EPI alone arrested the cells in S phase in HepG-2 cells, exposure to KSC and EPI simultaneously caused accumulation in the S phase, an effect caused by either KSC or EPI. Expression of cyclin A, Cdc25A and Cdk2 protein was down-regulated following exposure to KSC and EPI alone or in combination, exposure to KSC and EPI simultaneously resulting in the lowest values. Taken together, our findings suggest that KSC in combination with EPI might have potential as a new therapeutic regimen against HCC.

• Korean Journal of Materials Research
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• v.30 no.10
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• pp.542-549
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• 2020

Effects of Sc addition on microstructure, electrical conductivity, thermal conductivity and mechanical properties of the as-cast and as-extruded Al-2Zn-1Cu-0.3Mg-xSc (x = 0, 0.25, 0.5 wt%) alloys are investigated. The average grain size of the as-cast Al-2Zn-1Cu-0.3Mg alloy is 2,334 ㎛; however, this value drops to 914 and 529 ㎛ with addition of Sc element at 0.25 wt% and 0.5 wt%, respectively. This grain refinement is due to primary Al₃Sc phase forming during solidification. The as-extruded Al-2Zn-1Cu-0.3Mg alloy has a recrystallization structure consisting of almost equiaxed grains. However, the as-extruded Sc-containing alloys consist of grains that are extremely elongated in the extrusion direction. In addition, it is found that the proportion of low-angle grain boundaries below 15 degree is dominant. This is because the addition of Sc results in the formation of coherent and nano-scale Al₃Sc phases during hot extrusion, inhibiting the process of recrystallization and improving the strength by pinning of dislocations and the formation of subgrain boundaries. The maximum values of the yield and tensile strength are 126 MPa and 215 MPa for the as-extruded Al-2Zn-1Cu-0.3Mg-0.25Sc alloy, respectively. The increase in strength is probably due to the existence of nano-scale Al₃Sc precipitates and dense Al₂Cu phases. Thermal conductivity of the as-cast Al-2Zn-1Cu-0.3Mg-xSc alloy is reduced to 204, 187 and 183 W/MK by additions of elemental Sc of 0, 0.25 and 0.5 wt%, respectively. On the other hand, the thermal conductivity of the as-extruded Al-2Zn-1Cu-0.3Mg-xSc alloy is about 200 W/Mk regardless of the content of Sc. This is because of the formation of coherent Al₃Sc phase, which decreases Sc content and causes extremely high electrical resistivity.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2008.05a
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• pp.47-70
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• 2008

Cost efficiency is today the primary requirement in the paper and board industry. This has led therefore, to a greater preponderance of products with specifically designed functionality to take account of current industry needs. Continually increasing machine coating speeds together with these new coating colour components have put more emphasis on the importance of the correct rheology and water retention of the coating colours to achieve good runnability and end product quality. In the coating process, some penetration of the aqueous phase, to the base paper or board must occur to anchor the pre-coating to the base or the topcoat to the pre-coat. The aqueous phase acts as a vehicle not only for the binder, but also for the other components. If this water or material penetration is not controlled, there will be excessive material shift from the coating colour to the base, before immobilization of the coating colour will stop this migration. This can result in poor machine runnability, unstable system and uneven coating layer, impacting print quality. The performance of rheology modifiers or thickeners on the coating color have tended to be evaluated by the term, "water retention". This simple term is not sufficient to explain their performance changes during coating. In this paper we are introducing a new concept of "material retention", which takes note of the total composition of the coating colour material and therefore goes beyond the concept of only water retention. Controlled material retention leads to a more uniform z-directional distribution of coating colour components. The changes that can be made to z-directional uniformity will have positive effects on print quality as measured by surface strength, ink setting properties, print gloss, mottling tendency. Optical properties, such as light scattering, whiteness and light fastness delivery should also be improved. Additionally, controlled material retention minimizes changes to the coating colour with time in re-circulation giving less fluctuation in quality in the machine direction since it more closely resembles fresh coating for longer periods. Use of the material retention concept enables paper and board producers to have more stable runnability (i.e. lower process costs), improved end product quality (i.e. better performance of used chemicals) and/or optimized use of coating colour components (i.e. lower total formulation cost)

• Magazine of the Korean Society of Agricultural Engineers
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• v.34 no.3
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• pp.75-84
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• 1992

The paper manufactories in Sangpyeong Industrial Estates, Chinju, produce more than 80 tons of paper-mill sludge cakes every day, which costs about 840 million won for dump per year. Since the paper-mill sludge is biodegradable, the sludge can he utilized as an organic fertilizer if it is properly decomposed. This may lead to not only dramatic cut of the treatment cost but prevention from secondary environmental contamination due to dump. The primary objective of the study was to explore the quantitative range of major enviromental parameters influencing early composting of paper-mill cakes, naturally pretreated in warn and cold weather. The automatically-controlled reactor was designed, manufactured, and operated for nine days to decompose about 2201 of raw sludge cakes. Four tests(Test 1-Test 4) were implemented for the study of Phase I. Treatments of two levels of initial temperature (40˚C and 28˚C) and two levels of water content + C/N ratio (35% + 40 and 63% + 80) were made to test the significance of their parameters for decomposition of raw sludge cakes pretreated in warm weather. Another four tests (Test 5- Test 8) were implemented for the study of Phase II. Treatments of initial temperature and water content(W/C) + C/N ratio of raw sludge pretreated in cold weather were made to 16˚C and 13% +58 for Test 5, 6˚C and 53% +55 for Test 6, 7˚C and 36% +81 for Test 7, 31˚C and 30% +81 for Test 8. Natural weater condition(pretreatment condition) revealed the importance m composting of the paper-mill sludge cakes. Combination of water content adjustment to about 30% with C/N ratio amendment of about 20 and initial temperature of 30~40˚C was concluded to be the best for early composting of paper-mill sludge cakes with aeration rate and pH fixed. Temperature and C/N ratio were adapted as judging variables for composting degree. In addition, tests for microbial activity were performed to validate the experimental results. Since the temperature and C/N ratio did not coincide in some tests as judging variables for the maturity of the composting sludges, taking one of these parameters could mislead the concept of the maturity (composting conceptually new criterion to provide more reliable information for early composting of paper-mill sludge cakes.

• Journal of Korean Society for Geospatial Information Science
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• v.23 no.1
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• pp.73-79
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• 2015

Recently, BIM proliferates at high speeds so that BIM planning is trying to be used in various kinds of engineering. However, when using different software during design phase and construction phase, the problem of mutual compatibility is coming out. Even the BIM technology has been used or the practical applicability has been made into result, it would be fair to say that BIM has limitations in the visual level. In this research, it is meaningless to obtain the BIM result as the primary purpose. As the usefulness of it is judged incomplete, we committed to master the trend and problems of terrain spatial information systems and BIM. Furthermore, the plan of building the BIM in the civil field, especially the civil-BIM based on the technology ofterrain spatial information has been presented. It can be judged through this research that the high-capacity DB of BIM occurred during the whole process may cause poor performance of the following stage the structure system which connects the terrain spatial information and civil-BIM. In order to manage the optimal full cycle, the spatial analysis technology of the stages after choosing the DB has been described.

• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.4
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• pp.10-18
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• 2018

The primary purposes of this study are to understand a fundamental aspect of current uniformity around a reinforcing bar (rebar) in cement mortar, and to develop an accurate monitoring method in a wet-dry cycling process with the alternative current (AC) impedance method. Three cement mortar specimens with two embedded rebars were prepared in the laboratory. As a main variable, the distance between two rebars was designed to be 10, 20 and 30 mm with the same thickness of 20 mm. To simulate the corrosion of rebars in concrete structures in a marine environment, three cement mortar specimens were exposed to 15 wet-drying cycles (24-hour-immersion in seawater and 48-hour-drying in a room temperature) in the laboratory. It was observed that the potential level shifted to a noble value during corrosion potential monitoring, which is attributed to acceleration of dissolved oxygen diffusion at the drying process. AC impedance was measured in a frequency range from 100 kHz to 1 mHz on a wet-drying process. A theoretical model was proposed to explain the interface condition between the rebars and cement mortar by using the equivalent circuit consisting of a solution resistance, a charge transfer resistance and a CPE (constant phase element). It was observed that the diffusion impedance appeared in a low frequency range as corrosion of rebars progresses. At the drying stage of the wet-drying cycles, the currents line for monitoring tended to be non-uniform at the interface of rebar/mortar, being phase shift, ${\theta}$, close to $-45^{\circ}$.

• Journal of the Korean Magnetics Society
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• v.7 no.4
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• pp.173-179
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• 1997

Change in phases, microstructures, and magnetic properties by the variation of quench rate and heat treatment were investigated for melt-spun $Fe_{77}Pr_{15}C_8$ ribbons. The amorphization of as-spun ribbons increased as the quench rate increased. As a result, the ribbon quenched at 40 m/s was almost entirely amorphous. Similarly to cast alloys, the primary phase in crystalline ribbons quenched at 10 m/s was $\alpha$-Fe followed by the secondary $Fe_{17}Pr_2C_x$. Crystalline phases were still dominant in the ribbon spun at 20 m/s, but in this case crystallization of $Fe_{17}Pr_2C_x$ was remarkable with a little suppression of $\alpha$-Fe. At 30 m/s an amorphous phase obviously dominated in the as-spun ribbons with small fraction of crystals. Therefore, substantial amount of hard magnetic $Fe_{14}Pr_2C$ was not obtained from the as-spun state but, as in cast alloys, produced only by a solid-state transformation. Within a few minutes fine grains of $Fe_{14}Pr_2C$ were easily obtained at relatively low temperature when the degree of amorphization of as-spun ribbons was higher. The grain size of $Fe_{14}Pr_2C$ was well less than 1${\mu}{\textrm}{m}$. The ribbons quenched at 20 or 30 m/s yielded higher coercivities after heat treatment.

• Journal of Gastric Cancer
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• v.17 no.2
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• pp.132-144
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• 2017

Purpose: To identify baseline prognostic factors for survival in patients with disease progression, during or after chemotherapy for the treatment of advanced gastric or gastroesophageal junction (GEJ) cancer. Materials and Methods: We pooled data from patients randomized between 2009 and 2012 in 2 phase III, global double-blind studies of ramucirumab for the treatment of advanced gastric or GEJ adenocarcinoma following disease progression on first-line platinum- and/or fluoropyrimidine-containing therapy (REGARD and RAINBOW). Forty-one key baseline clinical and laboratory factors common in both studies were examined. Model building started with covariate screening using univariate Cox models (significance level=0.05). A stepwise multivariable Cox model identified the final prognostic factors (entry+exit significance level=0.01). Cox models were stratified by treatment and geographic region. The process was repeated to identify baseline prognostic quality of life (QoL) parameters. Results: Of 1,020 randomized patients, 953 (93%) patients without any missing covariates were included in the analysis. We identified 12 independent prognostic factors of poor survival: 1) peritoneal metastases; 2) Eastern Cooperative Oncology Group (ECOG) performance score 1; 3) the presence of a primary tumor; 4) time to progression since prior therapy <6 months; 5) poor/unknown tumor differentiation; abnormally low blood levels of 6) albumin, 7) sodium, and/or 8) lymphocytes; and abnormally high blood levels of 9) neutrophils, 10) aspartate aminotransferase (AST), 11) alkaline phosphatase (ALP), and/or 12) lactate dehydrogenase (LDH). Factors were used to devise a 4-tier prognostic index (median overall survival [OS] by risk [months]: high=3.4, moderate=6.4, medium=9.9, and low=14.5; Harrell's C-index=0.66; 95% confidence interval [CI], 0.64-0.68). Addition of QoL to the model identified patient-reported appetite loss as an independent prognostic factor. Conclusions: The identified prognostic factors and the reported prognostic index may help clinical decision-making, patient stratification, and planning of future clinical studies.

• The Journal of the Petrological Society of Korea
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• v.25 no.3
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• pp.261-281
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• 2016

Our knowledge of the lithosphere beneath the Korean Peninsula has been improved through petrologic and geochemical studies of upper mantle xenoliths hosted by Quaternary intraplate alkali basalts from Jeju Island. The xenoliths are mostly spinel lherzolites, accompanied by subordinate harzburgite and pyroxenites. The mantle xenoliths represent residual mantle material showing textural and geochemical evidence for at least a three-stage evolution, fractional partial melting, recrystallization, and metasomatism. Their composition primarily controlled by early fractional melt extraction and porphyroclastic and mylonitic fabrics formed in a shear-dominated environment, which was subsequently modified by residual slab-derived fluids (or melts). Modal metasomatic products occur as both anhydrous phase(orthopyroxene) and hydrous phase (phlogopite). Late-stage orthopyroxene is more common than phlogopite. However, chemical equilibrium is evident between the primary and secondary orthopyroxene, implying that the duration of post-metasomatic high temperatures enabled complete resetting/reequilibration of the mineral compositions. The metasomatic enrichment pre-dates the host Jeju Quaternary magmatism, and a genetic relationship with the host magmas is considered unlikely. Following enrichment in the peridotite protolith in the mantle wedge, the upper mantle beneath proto-Jeju Island was transformed from a subarc environment to an intraplate environment. The Jeju peridotites, representing old subarc fragments, were subsequently transported to the surface, incorporated into ascending Quaternary intraplate alkali basalt. The result of this study implies that long term material transfer in the transformation of geotectonic setting from a subarc to intraplate may have played a significant role in the evolution of lithospheric mantle, resulting in the enriched mantle domains, such as EM I or EM II in the lithospheric mantle beneath East Asia.

• Journal of Korea Foundry Society
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• v.41 no.3
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• pp.235-240
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• 2021

We present the effect of the critical cooling rate during rapid solidification on the nucleation of precipitates in an Fe₇₅B₁₃P₅Nb₂Hf₁C₄ (at.%) alloy. The thermophysical properties of the rapidly solidified Fe₇₅B₁₃P₅Nb₂Hf₁C₄ liquids, which were obtained at various cooling rates with various sizes of gas-atomized powder during a high-pressure inert gas-atomization process, were evaluated. The cooling rate of the small-particle powder (≤20 ㎛) was 8.4×10⁵ K/s, which was 13.5 times faster than that of the large-particle powder (20 to 45 mm; 6.2×10⁴ K/s) under an atomized temperature. A thermodynamic calculation model used to predict the nucleation of the precipitates was confirmed by the microstructural observation of MC-type carbide in the Fe₇₅B₁₃P₅Nb₂Hf₁C₄ alloy. The primary carbide phase was only formed in the large-particle gas-atomized powder obtained during solidification at a slow cooling rate compared to that of the small-particle powder.