• Journal of the Korean Ceramic Society
• /
• v.37 no.4
• /
• pp.320-326
• /
• 2000

Development of texture in SiC materials by hot-pressing and subsequent annealing was studied. Crystallographic texture type was characterized by measuring X-ray pole figures on the perpendicular plane to the hot-pressing direction. Observed all pole figures were nearly axially symmetric (fiber texture). In case of ${\beta}$-SiC materials, the pole density of basal plane (0004) increased as annealing time increased, in contrast, other planes (hkil) of ${\beta}$-SiC materials and all planes of ${\alpha}$-SiC materials nearly remained unchanged. In the case of ${\beta}$-SiC materials, therefore, a weak texture of (0001) plane at the normal direction took place in the 8h annealed samples, resulting from grian growth. The fracture toughness values of ${\alpha}$-SiC materials measured in both planes parallel and perpendicular to the hot-pressing direction were very similar. However, the fracture toughness of ${\beta}$-SiC materials measured parallel to the hot-pressing direction were higher than that measured perpendicular to the hot-pressing derection, relatively, because of the texture and the microstructure anisotropy.

• Journal of Life Science
• /
• v.7 no.3
• /
• pp.167-171
• /
• 1997

As an initial effort to elucidate RNA: protein binding in a way to regulate translation initiation and phosphorylation, a cDNA encoding a double-stranded RNA binding factor (RBFII)was isolated from Hela ZAPII cDNA library by affinity screening using [$\alpha$$^{-32}$P] UMP-labeled HIV Rev-responsive element(RRE) RNA. The nucleotide sequence of RBF (or TRBP) cDNA except the 5’end. At the 5’end, This common ORF was fused in-frame to N-terminal residues of Lac-Z through a unique 138 nt sequence encoding 46residues in the case of RBFII and a 63 nt sequence encoding 21 residuces in the case of RBFI. The context of ATG appearing first in the sequences suggests that both these cDNA inserts are incomplete at the 5’end.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.53 no.2
• /
• pp.70-75
• /
• 2016

This paper proposes the constructing method of effective multiplier based on the finite fields in case of P=2. The proposed multiplier is constructed by polynomial arithmetic part, mod F(${\alpha}$) part and modular arithmetic part. Also, each arithmetic parts can extend according to m because of it have modular structure, and it is adopted VLSI because of use AND gate and XOR gate only. The proposed multiplier is more compact, regularity, normalization and extensibility compare with earlier multiplier. Also, it is able to apply several fields in recent hot issue IoT configuration.

• Pediatric Gastroenterology, Hepatology & Nutrition
• /
• v.24 no.1
• /
• pp.109-117
• /
• 2021

Purpose: Ménétrier disease (MD) was first described in 1888, and 50 cases have been reported until now. We aimed to discuss the etiology, diagnostics, and management of MD in children. Methods: We searched for case reports published from 2014 till 2019 in English using PubMed. Articles were selected using subject headings and key words of interest to the topic. Interesting references of the included articles were also included. Results: The pathophysiology of MD is still uncertain. However, overexpression of transforming growth factor alpha with transformation of the gastric mucosa has been observed, which may be mediated by genetics and provoked by an infectious trigger. Clinically, MD is diagnosed by abdominal pain, vomiting, anorexia, and edema secondary to hypoalbuminemia. A gastroscopy with biopsy is the gold standard for the diagnosis of MD. In children, the disease is self-limiting and only requires supportive treatment. In general, children have a good prognosis and recover spontaneously within a few weeks. Conclusion: Few pediatric cases of MD have been described in recent years, and with all different etiology. Endoscopy with biopsy remains the golden standard for the diagnosis of MD, and in children, the disease is self-limiting.

• Journal of Life Science
• /
• v.23 no.9
• /
• pp.1140-1146
• /
• 2013

The effect of dried mackerel extract on the production of nitric oxide (NO) and cytokines, including interleukin-6 (IL-6), tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), and interferon-${\gamma}$ (IFN-${\gamma}$), was investigated. All extracts and fractions from dried mackerel significantly reduced NO production induced by lipopolysaccharide (LPS). Among the extracts, acetone+methylene chloride (A+M), n-hexane, and 85% aqueous methanol (MeOH) showed the strongest inhibitory effects. The 85% aqueous MeOH fraction at a concentration of $10{\mu}g$ significantly decreased LPS-induced IL-6 and TNF-${\alpha}$ production after 6 hr of incubation. In the case of LPS-induced IFN-${\gamma}$ production, the 85% aqueous MeOH fraction decreased the production of IFN-${\gamma}$ afer 6, 24, and 72 hr of incubation in a dose-dependent manner. The results show that an 85% aqueous MeOH fraction inhibits the production of NO and proinflammatory cytokines (IL-6, TNF-${\alpha}$, IFN-${\gamma}$), suggesting that this fraction acts as a potent immunomodulator.

• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.9 no.2
• /
• pp.260-265
• /
• 1999

$SiC/Si_3N_4$ composites were prepared by mixing ${\alpha}-Si_3N_4$ powder to $\alpha$-SiC powder in the range of 10 to 30 vol% with 10 vol% interval. 6 wt% of $Al_2O_3$ and $Y_2O_3$ were also added respectively as sintering aids. Then, pressureless sintering was performed at 1,78$0^{\circ}C$ for 2 hours in $N_2$ gas. In the case of adding 20 vol% of ${\alpha}-Si_3N_4$ powder, the relative desity to theoretical value and the flexutal strength were 92 % and 3,560 MPa, respectively. The smallest relative worn amount thereof was $2.68{\times}10^{-3}\;mm^2$ for 20 vol% ${\alpha}-Si_3N_4$. The composite containing 30 vol % of ${\alpha}-Si_3N_4$ powder showed the highest fracture toughness $(K_{1c})$ of $4.9\;MN/m^{3/2}$, although the reduction of the wear resistance due to the effect of the pores was observed.

• Korean Journal of Remote Sensing
• /
• v.29 no.2
• /
• pp.173-182
• /
• 2013

The early Sea-viewing Wide Field-of-view Sensor(SeaWiFS) atmospheric correction algorithm which is the basis of the atmospheric correction algorithm for Geostationary Ocean Color Imager(GOCI) assumes that water-leaving radiances is negligible at near-infrared(NIR) wavelengths. For this reason, all of the satellite measured radiances at the NIR wavelengths are assigned to aerosol radiances. However that assumption would cause underestimation of water-leaving radiances if it were applied to turbid Case-2 waters. To overcome this problem, Management Unit of the North Sea Mathematical Models(MUMM) atmospheric correction algorithm has been developed for turbid waters. This MUMM algorithm introduces new parameter ${\alpha}$, representing the ratio of water-leaving reflectance at the NIR wavelengths. ${\alpha}$ is calculated by statistical method and is assumed to be constant throughout the study area. Using this algorithm, we can obtain comparatively accurate water-leaving radiances in the moderately turbid waters where the NIR water-leaving reflectance is less than approximately 0.01. However, this algorithm still underestimates the water-leaving radiances at the extremely turbid water since the ratio of water-leaving radiance at two NIR wavelengths, ${\alpha}$ is changed with concentration of suspended particles. In this study, we modified the MUMM algorithm to calculate appropriate value for ${\alpha}$ using an iterative technique. As a result, the accuracy of water-leaving reflectance has been significantly improved. Specifically, the results show that the Root Mean Square Error(RMSE) of the modified MUMM algorithm was 0.002 while that of the MUMM algorithm was 0.0048.

• Asian Pacific Journal of Cancer Prevention
• /
• v.14 no.12
• /
• pp.7243-7249
• /
• 2013

Numerous studies have been conducted regarding association between TNF-${\alpha}$ and oral cancer risk, but the results remain controversial. The present meta-analysis is performed to acquire a more precise estimation of relationships. Databases of Pubmed, the Cochrane library and the China National Knowledge Internet (CNKI) were retrieved until August 10, 2013. Pooled odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated with fixed- or random-effect models. The heterogeneity assumption was assessed by I-squared test. Among the eight included case-control studies, all were focused on TNF-${\alpha}$-308G>A and four also concerned the TNF-${\alpha}$-238G>A polymorphism. It was found that oral cancer risk were significant decreased with the TNF-${\alpha}$-308G>A polymorphism in the additive genetic model (GG vs. AA, OR=0.19, 95% CI: [0.04, 1.00], P=0.05, I2=68.9%) and the dominant genetic model (GG+GA vs. AA, OR=0.22, 95% CI: [0.06, 0.82], P=0.03, I2=52.4%); however, no significant association was observed in allele contrast (G vs. A, OR=0.70, 95% CI: [0.23, 2.16], P=0.54, I2=95.9%) and recessive genetic models (GG vs. GA+AA, OR=0.72, 95% CI: [0.33, 1.57], P=0.41, I2=93.1%). For the TNF-${\alpha}$-238G>A polymorphism, significant associations with oral cancer risk were found in the allele contrast (G vs. A, OR=2.75, 95% CI: [1.25, 6.04], P=0.01, I2=0.0%) and recessive genetic models (GG vs. GA+AA, OR=2.23, 95%CI: [1.18, 4.23], P=0.01, I2=0.0%). Conclusively, this meta-analysis indicates that TNF-${\alpha}$ polymorphisms may contribute to the risk of oral cancer. Allele G and the GG+GA genotype of TNF-${\alpha}$-308G>A may decrease the risk of oral cancer, while allele G and the GG genotype of TNF-${\alpha}$-238G>A may cause an increase.

• Journal of the Korean Applied Science and Technology
• /
• v.31 no.4
• /
• pp.703-710
• /
• 2014

The following is the study result of herbal tea roasted at different temperatures between $80{\sim}140^{\circ}C$. Depending on treatment temperature the water content decreased, some carbonization occurred and crude ash content relatively increased. Also crude protein and crude fat decreased little. Solid elution rate of herbal tea showed 0.15~0.32%(w/w) and the rate of solid elution decreased with higher roasting temperature. There was no big change in $80{\sim}110^{\circ}C$ treatment section but the solid elution decreased rapidly in $110{\sim}140^{\circ}C$ section. The reason for decreasing solid elution rate at higher treatment temperature is because the compact inner tissue makes elution difficult. Benzopyrene content (0.29~0.51ppb) showed a tendency to increase with higher treating temperature. From this result, the $B({\alpha})P$ content differed depending on the treatment temperature and raw materials. In case of roasting, the actual inside temperature is around $200^{\circ}C$ but since the surface temperature of the roaster reaches around $2000^{\circ}C$ some portion of $B({\alpha})P$ content was presumed to be produced from the area that came in contact with this surface. When the processing which is a main component of food carbohydrate, protein, fat reason despite serve heat treatment as a whole is to be detected even though the $B({\alpha})P$ in this way is considered to be.

• Korean Journal of Food Science and Technology
• /
• v.45 no.3
• /
• pp.385-390
• /
• 2013

The effect of tuna extracts on the production of nitric oxide (NO) and cytokines including interleukin-6 (IL-6), tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), and interferon-${\gamma}$ (IFN-${\gamma}$), was investigated. All extracts and fractions from tuna significantly reduced NO production induced by lipopolysaccharide (LPS). The acetone+methylene chloride (A+M) extract, n-hexane and 85% aqueous methanol (MeOH) fractions had stronger inhibitory effects among them. The 85% aqueous MeOH fraction at a 10-${\mu}g$ concentration significantly decreased LPS-induced IL-6 and TNF-${\alpha}$ productions at 6 h of incubation. In the case of LPS-induced IFN-${\gamma}$ production, the 85% aqueous MeOH fraction at a 3-${\mu}g$ concentration showed significantly higher levels at 48 h of incubation. These results show that the 85% aqueous MeOH fraction inhibited the production of NO and pro-inflammatory cytokines (IL-6, TNF-${\alpha}$), suggesting that this fraction acts as a potent immunomodulator.