• IMMUNE NETWORK
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• v.10 no.3
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• pp.81-84
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• 2010

B cells, by virtue of their diverse roles in immune responses to foreign and self antigens, have become of increasing interest to the clinician as well as the basic immunologist. In particular, it is now apparent that the development of B cell unresponsiveness in antibody and T cell mediated autoimmune disorders and the transplant setting is both worthwhile and achievable.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.26 no.7A
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• pp.1152-1161
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• 2001

본 논문에서는 이동국 수신 신호의 SINR을 최대화하는 빔 성형 알고리듬을 이용하여, 폐쇄 루프 송신 빔 성형기술을 적용한 순방향 링크 CDMA 시스템에서의 안테나 수, 귀환 채널의 구조, 귀환 지연 등과 시스템 성능과의 상관관계를 연구하였다. 폐쇄 루프 전송 빔 성형에서는 이동국이 각 안테나가 겪는 채널을 추정하여 수신 SINR을 최대화시키는 가중치 벡터를 계산하고, 귀환채널을 통해 가중치 벡터의 양자화된 진폭과 위상정보를 전송한다. 컴퓨터 모의 실험 결과는 송신 안테나가 2개, 3개, 4개로 늘어남에 따라 빔 성형 이득은 단일 송신 안테나와 비교해 $10^{-5}$ BER 근방에서 4.2dB, 5.8dB, 7dB로 증가하지만 양자화 오류에 의한 성능 저하 또한 0.1dB, 0.6dB, 1.3dB로 커지는 것을 보여준다. 또한 순방향 채널의 최대 도플러 주파수가 100Hz일 때에는 귀환 채널을 통한 소신 가중치 벡터를 보다 빠르게 갱신하는 것이 가중치 벡터의 양자화 레벨의 수를 늘여주는 것보다 $10^{-5}$ BER 근방에서 0.6dB 더 좋은 성능을 보이며, 최대 도플러 주파수가 10Hz일 때에는 가중치 벡터의 갱신 속도를 늘이기 보다 양자화 레벨의 수를 늘여주어 정확한 가중치 벡터를 전송하는 편이 0.9dB의 성능 향상을 보인다. 두 전력제어 그룹 길이의 귀환지연으로 인한 성능저하는 채널의 최대 도플러 주파수가 50Hz인 경우가 채널의 최대 도플러 주파수가 100Hz인 경우보다 $10^{-5}$ BER 근방에서 0.3dB 정도 더 작다. 또한 AOS가 3$^{\circ}$인 경우가 AOS가 $10^{\circ}$인 경우보다 $10^{-5}$ BER 근방에서 1.9dB 정도, 주파수 선택적 페이딩 채널이 주파수 비선택적 페이딩 채널보다 $10^{-5}$ BER 근방에서 1dB 정도 귀환 지연으로 인한 성능의 저하가 작다.

• The Korean Journal of Emergency Medical Services
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• v.20 no.3
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• pp.57-67
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• 2016

Purpose: The purpose of this study was to investigate the knowledge and attitudes towards hepatitis B among paramedic students. Methods: A self-reported questionnaire was completed by 395 paramedic students in Daejeon and Chungnam from May 10 to June 10, 2016. The questionnaire consisted of general characteristics of the subjects (9 items), knowledge of hepatitis B (20 items), and attitudes towards hepatitis B (7 items). Data were analyzed by t test, ANOVA, post hoc Duncan test, and Pearson's correlation analysis using SPSS v. 23.0. Results: The knowledge of hepatitis B was 10.52(${\pm}5.18$) out of 20 points and was significantly correlated with grade, vaccination, or antibody-positive irerspective of education. The positive attitude toward hepatitis B was 3.15(${\pm}.43$) and there was a significant correlation with family history irrespective of education. There was a statistically positive correlation between the knowledge and attitudes towards hepatitis B (r=.104, p=.039). Conclusion: Precise knowledge delivery and full understanding of hepatitis B should be incorporated into the education of paramedic students. Active infection control by emergency medical technicians should be maintained by hepatitis B prevention practices.

• YAKHAK HOEJI
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• v.52 no.6
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• pp.488-493
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• 2008

2-Aminothiazole ring as a bioisoster of catechol in dopamine has provided with good oral availability and lipophilic property. 2-Aminoindan, is a rigid form of dopamine, was evaluated as a dopamine D3 agonist with low neurotoxicity. Dopamine D3 agonist was evaluated as selective for the treatment of Parkinson's disease. In order to develop a novel dopamine D3 agonist, we tried to synthesize the aminothiazoloindenoxazine derivative that is a hybrid structure of aminoindenoxazine and thiazole ring. cis-2-Amino-1-indanol (2) was synthesized from 1,2-indandione-2-oxime by catalytic hydrogenation and it was treated with chloroacetyl chloride and NaH in benzene solution to give (${\pm}$)-cis-4,4a,5,9b-tetrahydroindeno[1,2-b][1,4]oxazin-3(2H)-one (6). Nitration of 6 by the mixed acid gave 8-nitro compound (7) and the carbonyl group of 7 was reduced with $LiAlH_4$ to afford compound (8). 8 was reduced to form (${\pm}$)-cis-8-amino-2,3,4,4a,5,9b-hexahydroindeno[1,2-b][1,4]oxazine (9) and finally it was cyclized with KSCN in glacial acetic acid to yield (${\pm}$)-cis-8-amino-2,3,4,4a,5,10b-hexahydrothiazolo[4,5-f]indeno[1,2-b][1,4]oxazine (10).

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.10
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• pp.1731-1736
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• 2008

In this paper, singly fed circularly polarized nearly-square patch antenna for receiving S-DMB is presented. It used teflon substrate of relative dielectric constant ${\in}_{\gamma}=2.2$ and the sire is $40{\times}40{\times}15[mm]$. Experimental results of fabricated antenna show that input return loss and axial ratio are about 22MHz, 25MHz at the center resonant frequency, respectively. And fabricated LNA has gain of 27.5 [dB], NF of 1.27 [dB], input return loss of -15.4 [dB] and output return loss of -18.9 dB, respectively. Simulation results and experimental results are good agreements. This proposed antenna is well able to handheld gadgets for receiving S-DMB.

• Microbiology and Biotechnology Letters
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• v.52 no.1
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• pp.1-14
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• 2024

This study focused on isolating and identifying strains from the gut of Epinephelus akaara cultivated in aquaculture facilities on Jeju Island. The aim was to evaluate the potential of utilizing these strains as probiotics for industrial applications. A total of 129 strains were isolated from the gut of E. akaara and screened based on their ability to create a clear zone of 10 mm or more in a preliminary antimicrobial activity test. Twelve strains were selected for further analysis, including bile resistance, acid tolerance at different pH levels, antioxidant activity, antibiotic susceptibility, and biochemical characteristics using the API kit. Through these characteristic experiments, eight strains (G1, G3, G15, G21, B1, B2, B3, B5) were identified as having potential as probiotics. Among these, the B group strains (B1, B2, B3, B5) exhibited significantly higher activity compared to the G group strains (G1, G3, G15, G21). Based on the phylogenetic analysis of the 16S rRNA gene sequences of the selected microorganisms, the strains were named as follows: B1 strain as Lactobacillus paracasei B1, B2 strain as Lactococcus lactis B2, B3 strain as Lactobacillus plantarum B3, B5 strain as Lactococcus lactis subsp. hordniae B5, G1 strain as Bacillus licheniformis G1, G3 strain as Bacillus velezensis G3, G15 strain as Brevibacterium frigoritolerans G15, and G21 strain as Bacillus pumilus G21.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1252_1253
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• 2009

The composites were fabricated by adding 0, 15, 20, 25[vol.%] Zirconium Diboride(hereafter, $ZrB_2$) powders as a second phase to Silicon Carbide(hereafter, SiC) matrix. The physical, mechanical and electrical properties of electroconductive SiC ceramic composites by spark plasma sintering(hereafter, SPS) were examined. Reactions between $\beta$-SiC and $ZrB_2$ were not observed in the XRD analysis The relative density of mono SiC, SiC+15[vol.%]$ZrB_2$, SiC+20[vol.%]$ZrB_2$ and SiC+25[vol.%]$ZrB_2$ composites are 90.97[%], 74.62[%], 77.99[%] and 72.61[%] respectively. The XRD phase analysis of the electroconductive SiC ceramic composites reveals high of SiC and $ZrB_2$ and low of ZrO2 phase. The electrical resistivity of mono SiC, SiC+15[vol.%]$ZrB_2$, SiC+20[vol.%]$ZrB_2$ and SiC+25[vol.%]$ZrB_2$ composites are $4.57{\times}10^{-1}$, $2.13{\times}10^{-1}$, $1.53{\times}10^{-1}$ and $6.37{\times}10^{-2}[{\Omega}{\cdot}cm]$ at room temperature, respectively. The electrical resistivity of mono SiC, SiC+15[vol.%]$ZrB_2$, SiC+20[vol.%]$ZrB_2$ and SiC+25[vol.%]$ZrB_2$ are Negative Temperature Coefficient Resistance(hereafter, NTCR) in temperature ranges from 25[$^{\circ}C$] to 100[$^{\circ}C$]. It is convinced that SiC+20[vol.%]$ZrB_2$ composite by SPS can be applied for heater above 1000[$^{\circ}C$].

• YAKHAK HOEJI
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• v.41 no.6
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• pp.789-796
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• 1997

The purpose of this study was to determine the effect of sulfinpyrazone on fumonisin $B_1$-induced elevation of free sphingoid bases in LLC-$PK_1$ cells. Fumonis ins are a family of mycotoxins produced by the fungi Fusarium moniliforme which is common contaminant in corn. Fumonisins are also potent inhibiors of sphingosine and sphinganine N-acyltransferases (ceramide synthases), key enzymes in sphingolipid metabolism resulting in the elevation of free sphinganine. The cytosolic concentration of fumonisin B1 was known to be closely proportional to the elevation of free sphinganine in LLC-PK1 cells [Yoo, H.-S., Norred, W.P., Wang, E., Merrill, A.H., Jr., and Riley, R.T. (1992) Toxicol. Appl.Pharmacol. 114. 9-15]. Sulfinpyrazone, an anion transport inhibitor, reduced the elevated level of free sphinganine resulting from fumonisin B1 inhibition of de novo sphingolipid biosynthesis. Fumonisin B1 at a concentration of 20${\mu}$M showed approximately 120pmol/$10^6$ cells relative to 3-10pmol/$10^6$ cells in control cultures, and sulfinpyrazone at a concentration of 200${\mu}$M partially reversed the increased level of free sphinganine induced by fumonisin $B_1$ down to normal level after exposure to fumonisin $B_1$ for 8 to 24hr. However, the reduced effect of sulfinpyrazone on the fumonisin $B_1$-induced elevation of intracellular sphinganine was not shown after 24hr. Fumonisin $B_1$ exposure to LLC-PK1 cells for 36 and 48hr showed approximately 74 and 80pmol per $10^6$ cells relative to 82 and 76pmol,respectively, in fumonisin $B_1$ plus sulfinpyrazone-treated cultures. Sulfinpyrazone-induced less elevation of free sphinganine in confluent cells after exposure to fumonisin $B_1$ suggested that either sulfinpyrazone may block the availability of fumonisin $B_1$ to cells or act on the fumonisin $B_1$ interaction with ceramide synthase.

• Korean Journal of Food Science and Technology
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• v.39 no.3
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• pp.323-329
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• 2007

We investigated the immunomodulatory actions of water extract from Acanthopanax senticosus in male ICR mice. The mice were treated with fermented milk containing three added doses of freeze dried extract: 3 mg/kg (A), 9 mg/kg (B), and 27 mg/kg (C) of body weight with Acanthopanax senticosus: Codonopsis lanceolata (8:2) for 7 and 10 weeks, respectively. Organ weights, plaque-forming cell tests, agglutination tests, IgG tests, differential white cell counts, and histological tests were performed at the 7th and 10th weeks of dietary treatment. There were no significant differences in body weight and organ weight. The spleen indices of group B at 7 weeks and group C at 10 weeks were significantly higher than those of the control group (p<0.05). For the plaque-forming cell test, groups B and C at 7 weeks, and group C at 10 weeks, showed significant increases over the control group (p<0.05). The agglutination test decreased with an extended experimental period. Groups A, B, and C at 7 weeks, and groups B and C at 10 weeks, had greater antibody responses to sheep red blood cells (SRBC) than the control group. The IgG antibody production of group C at 7 weeks and groups B and C at 10 weeks were significantly higher than the control group (p<0.05). In groups B and C, lymphocyte percentage was higher than the control group, and their spleen and thymus tissues showed active immune reactions.

• IMMUNE NETWORK
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• v.10 no.6
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• pp.247-249
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• 2010

Foxp3 is a transcript factor for regulatory T cell development. Interestingly, Foxp3-expressing cells were identified in B cells, especially in CD19(+)CD5(+) B cells, while those were not examined in CD19(+)CD5(-) B cells. Foxp3-expressing CD5(+) B cells in this study were identified in human PBMCs and were found to consist of $8.5{\pm}3.5%$ of CD19(+)CD5(+) B cells. CD19(+)CD5(+)Foxp3(+) B cells showed spontaneous apoptosis. Rare CD19(+)CD5(+) Foxp3(+) regulatory B cell (Breg) population was unveiled in human peripheral blood mononuclear cells and suggested as possible regulatory B cells (Breg) as regulatory T cells (Treg). The immunologic and the clinical relevant of Breg needs to be further investigated.