• Title/Summary/Keyword: $\alpha$-SiC

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Antioxidative Properties of Mackerel Scomber japonicus Fed a Diet Fortified with Conjugated Linoleic Acid and Ascidian Halocynthia roretzi Tunic Extract (멍게껍질 추출색소 및 CLS (Conjugated Linoleic Acid)가 함유된 사료를 섭취한 고등어 (Scomber japonicus)의 항산화 활성)

  • Park, Eun-Jung;Park, Si-Hyang;Kang, Seok-Joong;Ha, Yeong-Lae;Choi, Yeung-Joon;Choi, Byeong-Dae
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.44 no.3
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    • pp.183-190
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    • 2011
  • This study was performed to assess the antioxidative properties of lipid from aquacultured mackerel Scomber japonicus fed with a diet fortified with conjugated linoleic acid (CLA) and ascidian Halocynthia roretzi tunic extracts by radical scavenging assay. The fish were separated into squid oil (Control) and 2.5% CLA (CA25) groups during the 8-week feeding period. The reducing power of each sample showed high levels of activity compared with ${\alpha}$-tocopherol and butylated-hydroxyanisol (BHA) at 0.2-1.0 mg/mL of lipid. Inhibition of linoleic acid oxidation in samples from Control and CA25 groups showed similar activity after 2 days of incubation at $40^{\circ}C$. The 2,2-diphenyl-1-picrylhydrazyl (DPPH), superoxide, and hydroxyl radical scavenging activities of CLA and carotenoid-deposited sample (CA25) were higher than those of the Control group. The results indicated that the lipid extracted from the viscera of mackerel showed slightly higher antioxidant activities than that from the muscle.

Separation of $CO_2$ and $N_2$ with a NaY Zeolite Membrane under Various Permeation Test Conditions

  • Cho, Churl-Hee;Yeo, Jeong-Gu;Ahn, Young-Soo;Han, Moon-Hee;Hyun, Sang-Hoon
    • Korean Membrane Journal
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    • v.8 no.1
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    • pp.21-30
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    • 2006
  • A faujasite NaY zeolite membrane was prepared on a tubular ${\alpha}-Al_2O_3$ support by the secondary growth process, and effects of permeation test conditions on the $CO_2/N_2$ separation were investigated. A NaY zeolite membrane with good $CO_2/N_2$ separation was successfully synthesized by using the hydrothermal solution ($Al_2O_3:SiO_2:Na_2O:H_2O$ = 1:6:14:840 in a molar base): at a permeation temperature of $30^{\circ}C$, its $CO_2$ permeance and $CO_2/N_2$ separation factor were $2.5{\times}10^{-7}mol/m^2secPa$ and 34, respectively. The $CO_2$ and $N_2$ permeations were highly dependent on permeation test conditions (feed composition, feeding rate, feed pressure, He sweeping rate and permeation temperature). The results indicated that (i) $CO_2$ and $N_2$ permeations through NaY zeolite membrane are governed by surface and micropore diffusions, respectively, (ii) the preparation of NaY zeolite membrane with a large permeating area is one of the most difficult hurdles for its real applications, and (iii) the retardation of $N_2$ permeation is an effective key to improve $CO_2/N_2$ separation factor in NaY zeolite membrane.

Effect of Pine needle Ethanol Extracts on the Inhibitory Activity of Atopic Dermatitis (송엽 에탄올 추출물의 아토피 저해 활성)

  • Jeong, Da-Hyun;Kim, Koth-Bong-Woo-Ri;Jung, Seul-A;Kim, Hyun-Jee;Kang, Bo-Kyeong;Bark, Si-Woo;Kim, Tae-Wan;Ahn, Dong-Hyun
    • KSBB Journal
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    • v.28 no.2
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    • pp.123-130
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    • 2013
  • The aim of this study was to examine inhibitory effects of pine needle ethanol extracts (PNEE) on atopic dermatitis (AD). To determine inflammatory activity PNEE was added to LPS-induced murine peritoneal macrophages for an in-vitro test. In addition, anti-AD test was carried out by spreading PNEE on the dorsal skin of 2,4-dinitrochlorobenzene (DNCB)- induced BALB/c mice. It was confirmed that the nitric oxide (NO) secretion was suppressed when $1{\sim}50{\mu}g/mL$ of PNEE were added to LPS-induced murine peritoneal macrophages. Moreover, levels of TNF-${\alpha}$, IL-6, and IL-$1{\beta}$, were decreased. For the anti-AD test, PNEE alleviated symptoms of the erythema in DNCB-induced mice. Furthermore, the IFN-${\gamma}$ secretion of the group treated with PNEE was increased in splenocytes from DNCB-induced mice compared to the positive control, while IL-4 secretion diminished. Through these results, we can conclude that PNEE can inhibit AD by modulating the IFN-${\gamma}$, IL-4 cytokines production and inhibiting inflammation.

Chemical Mechanical Polishing: A Selective Review of R&D Trends in Abrasive Particle Behaviors and Wafer Materials (화학기계적 연마기술 연구개발 동향: 입자 거동과 기판소재를 중심으로)

  • Lee, Hyunseop;Sung, In-Ha
    • Tribology and Lubricants
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    • v.35 no.5
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    • pp.274-285
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    • 2019
  • Chemical mechanical polishing (CMP), which is a material removal process involving chemical surface reactions and mechanical abrasive action, is an essential manufacturing process for obtaining high-quality semiconductor surfaces with ultrahigh precision features. Recent rapid growth in the industries of digital devices and semiconductors has accelerated the demands for processing of various substrate and film materials. In addition, to solve many issues and challenges related to high integration such as micro-defects, non-uniformity, and post-process cleaning, it has become increasingly necessary to approach and understand the processing mechanisms for various substrate materials and abrasive particle behaviors from a tribological point of view. Based on these backgrounds, we review recent CMP R&D trends in this study. We examine experimental and analytical studies with a focus on substrate materials and abrasive particles. For the reduction of micro-scratch generation, understanding the correlation between friction and the generation mechanism by abrasive particle behaviors is critical. Furthermore, the contact stiffness at the wafer-particle (slurry)-pad interface should be carefully considered. Regarding substrate materials, recent research trends and technologies have been introduced that focus on sapphire (${\alpha}$-alumina, $Al_2O_3$), silicon carbide (SiC), and gallium nitride (GaN), which are used for organic light emitting devices. High-speed processing technology that does not generate surface defects should be developed for low-cost production of various substrates. For this purpose, effective methods for reducing and removing surface residues and deformed layers should be explored through tribological approaches. Finally, we present future challenges and issues related to the CMP process from a tribological perspective.

Cordycepin from Medicinal Fungi Cordyceps militaris Mitigates Inflammaging-Associated Testicular Damage via Regulating NF-κB/MAPKs Signaling in Naturally Aged Rats

  • Kopalli, Spandana Rajendra;Cha, Kyu-Min;Cho, Jae Youl;Kim, Si-Kwan;Koppula, Sushruta
    • Mycobiology
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    • v.50 no.1
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    • pp.86-95
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    • 2022
  • Inflammaging in male reproductive organs covers a wide variety of problems, including sexual dysfunction and infertility. In this study, the beneficial effects of cordycepin (COR), isolated from potential medicinal fungi Cordyceps militaris, in aging-associated testicular inflammation and serum biochemical changes in naturally aged rats were investigated. Male Sprague Dawley rats were divided into young control (YC), aged control (AC), and COR (5, 10, and 20 mg/kg) treated aged rat groups. Aging-associated serum biochemical changes and inflammatory parameters were analyzed by biochemical assay kits, Western blotting, and real-time RT-PCR. Results showed a significant (p < 0.05) alteration in the total blood cell count, lipid metabolism, and liver functional parameters in AC group when compared with YC group. However, COR-treated aged rats ameliorated the altered biochemical parameters significantly (p < 0.05 and p < 0.01 at 5, 10, and 20 mg/kg, respectively). Furthermore, the increase in the expression of inflammatory mediators (COX-2, interleukin (IL)-6, IL-1β, and tissue necrosis factor-alpha) in aged rat testis was significant (p < 0.05) when compared with YC group. Treatment with COR at 20 mg/kg to aged rats attenuated the increased expression of inflammatory mediators significantly (p < 0.05). Mechanistic studies revealed that the potential attenuating effects exhibited by COR in aged rats was mediated by regulation of NF-κB activation and MAPKs (c-Jun N-terminal kinase, extracellular signal-regulated kinase 1/2, and p38) signaling. In conclusion, COR restored the altered serum biochemical parameters in aged rats and ameliorated the aging-associated testicular inflammation proving the therapeutic benefits of COR targeting inflammaging-associated male sexual dysfunctions.

Hypoxia-inducible factor 1α inhibitor induces cell death via suppression of BCR-ABL1 and Met expression in BCR-ABL1 tyrosine kinase inhibitor sensitive and resistant chronic myeloid leukemia cells

  • Masanobu Tsubaki;Tomoya Takeda;Takuya Matsuda;Akihiro Kimura;Remi Tanaka;Sakiko Nagayoshi;Tadafumi Hoshida;Kazufumi Tanabe;Shozo Nishida
    • BMB Reports
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    • v.56 no.2
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    • pp.78-83
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    • 2023
  • Chronic myeloid leukemia (CML) has a markedly improved prognosis with the use of breakpoint cluster region-abelson 1 (BCR-ABL1) tyrosine kinase inhibitors (BCR-ABL1 TKIs). However, approximately 40% of patients are resistant or intolerant to BCR-ABL1 TKIs. Hypoxia-inducible factor 1α (HIF-1α) is a hypoxia response factor that has been reported to be highly expressed in CML patients, making it a therapeutic target for BCR-ABL1 TKI-sensitive CML and BCR-ABL1 TKI-resistant CML. In this study, we examined whether HIF-1α inhibitors induce cell death in CML cells and BCR-ABL1 TKI-resistant CML cells. We found that echinomycin and PX-478 induced cell death in BCR-ABL1 TKIs sensitive and resistant CML cells at similar concentrations while the cell sensitivity was not affected with imatinib or dasatinib in BCR-ABL1 TKIs resistant CML cells. In addition, echinomycin and PX-478 inhibited the c-Jun N-terminal kinase (JNK), Akt, and extracellular-regulated protein kinase 1/2 (ERK1/2) activation via suppression of BCR-ABL1 and Met expression in BCR-ABL1 sensitive and resistant CML cells. Moreover, treatment with HIF-1α siRNA induced cell death by inhibiting BCR-ABL1 and Met expression and activation of JNK, Akt, and ERK1/2 in BCR-ABL1 TKIs sensitive and resistant CML cells. These results indicated that HIF-1α regulates BCR-ABL and Met expression and is involved in cell survival in CML cells, suggesting that HIF-1α inhibitors induce cell death in BCR-ABL1 TKIs sensitive and resistant CML cells and therefore HIF-1α inhibitors are potential candidates for CML treatment.

Mineralogical Characteristics of the Noro and Miag Series Soils Developed on the Cinder Cones in Jeju Island (제주도(濟州道) 산록(山麓)의 분석구(噴石丘)에서 발달(發達)된 노로통과 미악통 토양(土壤)의 광물학적(鑛物學的) 특성(特性))

  • Zhang, Yong-Seon;Kim, Yoo-Hak;Song, Kwan-Cheol;Kim, Sun-Kwan
    • Korean Journal of Soil Science and Fertilizer
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    • v.35 no.3
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    • pp.145-152
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    • 2002
  • The composition of primary minerals in the rocks and secondary minerals of clay fractions of the soil developed on the cinder cones in the foot of Halla Mt., Jeju Island was investigated. The effects of parent materials on the physico-chemical properties and mineralogical characteristics were evaluated by XRD, DTA with the chemical composition of $H^+$ saturated clays. The main rock-forming minerals of a residual cinder cones were plagioclase with subsidiary minerals of hematite, gibbsite and quartz in the red cinder cone and of augite, quartz, feldspars and olivine in black cinder cone. It is demonstrated that ignition loss and sesquioxides content were higher in the red cinder soil than black cinder, which was resulted in the intermittent eruption of volcanic activity. For the chemical analysis of whole soils, $SiO_2/Al_2O_3$ ratio was increased from 2 to 3, but Ignition loss is decreased and $K_2O$ content are very low with increasing the soil depth in regard to the composition and kinds of clay minerals. No clay formation from micas mineral were in volcanic ashes. Dominant clay minerals of the cinder cone soils as a black and red cinder cone soil were allophane with some quartz and feldspars, while vermiculite, illite, kaolin were coexisted as a subsidiary minerals. But the red cinder cones soils had more hematite and gibbsite of the clay fractions than the black soils with magnetite. The exothermic pick of DTA at about $660^{\circ}C$ for cinder cone soils might be corresponded the oxidation magnetite to hematite reation. With regarding to the compositions of mineral detected by X-ray diffractogram and the properties of minerals by D.T.A thermogram, the dominant clay mineral was allophane of the cinder cone soils with some ferrous compounds, red colour of the cinder cone soils which are originated in hematite.

Polymorphisms and Functional Analysis of the Intact Human Papillomavirus16 E2 Gene

  • Ekalaksananan, Tipaya;Jungpol, Watcharapol;Prasitthimay, Chuthamas;Wongjampa, Weerayut;Kongyingyoes, Bunkerd;Pientong, Chamsai
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.23
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    • pp.10255-10262
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    • 2015
  • High risk human papillomavirus (HR-HPV) E2 proteins play roles in transcriptional regulation and are commonly functionally disrupted when the HPV genome integrates into host chromosomes. Some 15-40% of cancer cases, however, contain an intact E2 gene or episomal HPV. In these cases, polymorphism of the E2 gene might be involved. This study aimed to determine polymorphisms of the E2 gene in episomal HPV16 detected in high grade squamous intraepithelial lesions and squamous cell carcinomas and altered functions compared to the E2 prototype. The E2 gene was amplified and sequenced. Two expression vectors containing E2 gene polymorphisms were constructed and transfected in SiHa and C33A cells, then E6 gene as well as Il-10 and TNF-${\alpha}$ expression was determined by quantitative RT-PCR. Expression vectors and reporter vectors containing the HPV16 long control region (LCR) were co-transfected and transcriptional activity was determined. The results showed that a total of 32 nucleotides and 23 amino acids were changed in all 20 cases of study, found in the transactivation (TA) domain, hinge (H) region and DNA binding (DB) domain with 14, 5 and 13 nucleotide positions. They mostly caused amino acid change. The expressing vectors containing different E2 gene polymorphisms showed E6 mRNA suppression, TNF-${\alpha}$ mRNA suppression and IL-10 induction but no statistically significant differences when compared to the E2 prototype. Moreover, promoter activity in HPV16 LCR was not affected by E2 protein with different gene polymorphisms, in contrast to nucleotide variations in LCR that showed an effect on transcription activity. These results demonstrated that E2 gene polymorphisms of episomal HPV16 did not affect transcriptional regulation and suggested that nucleotide variation as well as epigenetic modification of the LCR might play a role in inducing malignant transformation of cells containing episomal HPV16.

A Study on Temperature Dependence of Tunneling Magnetoresistance on Plasma Oxidation Time and Annealing Temperature (플라즈마 산화시간과 열처리 조건에 따른 터널링 자기저항비의 온도의존특성에 관한 연구)

  • Kim, Sung-Hoon;Lee, Seong-Rae
    • Journal of the Korean Magnetics Society
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    • v.14 no.3
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    • pp.99-104
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    • 2004
  • We have studied to understand the barrier and interface qualities and structural changes through measuring temperature dependent spin-polarization as functions of plasma oxidation time and annealing time. Magnetic tunnel junctions consisting of SiO2$_2$/Ta 5/CoFe 17/IrMn 7.5/CoFe 5/Al 1.6-Ox/CoFe 5/Ta 5 (numbers in nm) were deposited and annealed when necessary. A 30 s,40 s oxidized sample showed the lowest spin-polarization values. It is presumed that tunneling electrons were depolarized and scattered by residual paramagnetic Al due to under-oxidation. On the contrary, a 60s, 70 s oxidized sample might have experienced over-oxidation, where partially oxidized magnetic dead layer was formed on top of the bottom CoFe electrode. The magnetic dead layer is known to increase the probability of spin-flip scattering. Therefore it showed a higher temperature dependence than that of the optimum sample (50 s oxidation). temperature dependence of 450 K annealed samples was improved when the as-deposited one compared. But the sample underwent 475 K and 500 K annealing exhibits inferior temperature dependence of spin-polarization, indicating that the over-annealed sample became microstucturally degraded.

The Physicochemical Properties of Seed Mash Prepared with Koji (Koji를 이용한 seed mash의 이화학적 특성)

  • Lee, Myung-Koo;Park, Jung-Kil;Lee, Si-Kyung
    • Korean Journal of Food Science and Technology
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    • v.37 no.2
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    • pp.199-205
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    • 2005
  • Physicochemical quality characteristics of seed mashes were investigated for development of new creative breadmaking in bakery. Aridity of seed mashes fermented with Koji, lactic acid bacteria, and baker's yeast was slightly lower than those fermented with Koji and yeast. ${\alpha}-Amylase$, saccharifying amylase, and acidic protease activities of seed mash composed of water (560 mL) and Koji (400 g) were 0.26 SKB, 36 SP, and 645 HUT/g, respectively. Reducing sugar content of seed mash made with Koji increased up to 13.04% after 36 hr fermentation, then decreased drastically thereafter, whereas that of seed mashes made with Koji, yeast, and lactic acid bacteria increased up to 6.5% at 6 hr, decreased to 1 to 2.5% at 12 hr, and remained less than 0.7% after 18 hr fermentation. Total organic acid contents were 10.4-12.25mg/mL. Flavor compounds including ethyl acetate, ethyl caprylate, isoamyl acetate, and p-vinyl guaiacol were detected in seed mash fermented with Koji, yeast, and L. brevis. These results show use of seed mash fermented with Koji, S. cerevisiae, and lactic acid bacteria enhances bread flavor.