• Membrane Journal
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• v.23 no.4
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• pp.290-296
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• 2013

Poly(vinylidenefluoride-co-chlorotrifluoroethylene) P(VDF-co-CTFE) polymer was attached to methacrylic acid (MAA) in the presence of 1,8-diazabicyclo[5,4,0]undec-7-ene(DBU) catalyst to prepare P(VDF-co-CTFE)-MAA copolymer. The modified P(VDF-co-CTFE)-MAA was polymerized with 2-sulfoethyl methacrylate (SEMA) monomer in the presence of 4',4'-azobis(4-cyanovaleric acid(ACVA) initiator by free radical polymerization to form the proton conducting membrane. The ratio of the SEMA was increased in the membrane to increase the presence of the acidic group. The maximum IEC value that was observed at 50% SEMA was around 0.82 meq/g, which is consistent with the water uptake value. The highest proton conductivity achieved by P(VDF-co-CTFE)-MAA/SEMA membrane with 50% SEMA was approximately 0.041 S/cm. This indicates that the available ionic group for the proton conduction increases with the increase in the SEMA in the membrane.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.10
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• pp.5883-5890
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• 2013

Previously, we demonstrated overexpression of semaphorin4D (SEMA4D, CD100) to be closely related to tumor angiogenesis in epithelial ovarian cancers (EOCs). However, the function and expression of SEMA4D in the EOC microenvironment has yet to be clarified in detail. In this study, we confirmed that overexpression of SEMA4D in primary tumors and ascites was related to low differentiation, platinum resistance and a refractory status (P<0.05), while high M2 macrophage count and percentage were evident in EOC patients with advanced FIGO stage and platinum resistance (P<0.05), using immunohistochemistry, enzyme-linked immunosorbent assay (ELISA), and fluorescence-activated cell sorting (FACS), respectively. The data showed correlations of SEMA4D expression and M2 macrophage counts in primary tumors and M2 macrophage percentage in ascites (r=0.281 and 0.355, each P<0.05). In the Cox proportional hazard mode, SEMA4D expression was an independent indicator of overall survival (OS) and progression-free survival (PFS) for EOC patients. Furthermore, higher expression of SEMA4D in ovarian cancer cell lines (SKOV3, A2780, and SW626) and their supernatants were found than that in a human primary cultured ovarian cell and its supernatant by reversed transcript PCR (RT-PCR), Western blotting and ELISA, respectively. Interestingly, peripheral blood monocytes (MOs) tended towards the M2-polarized macrophage phenotype ($CD163^{high}$) in vitro after human recombined soluble SEMA4D protein stimulation. These findings suggest that SEMA4D might possibly serve as a reliable tool for early and accurate prediction of EOC poor prognosis and could playan important role in promoting tumor dissemination and metastasis in the EOC microenvironment. Thus SEMA4D and its role in macrophage polarization in EOC warrants further study.

• Molecules and Cells
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• v.43 no.3
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• pp.228-235
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• 2020

The Drosophila transmembrane semaphorin Sema-1a mediates forward and reverse signaling that plays an essential role in motor and central nervous system (CNS) axon pathfinding during embryonic neural development. Previous immunohistochemical analysis revealed that Sema-1a is expressed on most commissural and longitudinal axons in the CNS and five motor nerve branches in the peripheral nervous system (PNS). However, Sema-1a-mediated axon guidance function contributes significantly to both intersegmental nerve b (ISNb) and segmental nerve a (SNa), and slightly to ISNd and SNc, but not to ISN motor axon pathfinding. Here, we uncover three cis-regulatory elements (CREs), R34A03, R32H10, and R33F06, that robustly drove reporter expression in a large subset of neurons in the CNS. In the transgenic lines R34A03 and R32H10 reporter expression was consistently observed on both ISNb and SNa nerve branches, whereas in the line R33F06 reporter expression was irregularly detected on ISNb or SNa nerve branches in small subsets of abdominal hemisegments. Through complementation test with a Sema-1a loss-of-function allele, we found that neuronal expression of Sema-1a driven by each of R34A03 and R32H10 restores robustly the CNS and PNS motor axon guidance defects observed in Sema-1a homozygous mutants. However, when wild-type Sema-1a is expressed by R33F06 in Sema-1a mutants, the Sema-1a PNS axon guidance phenotypes are partially rescued while the Sema-1a CNS axon guidance defects are completely rescued. These results suggest that in a redundant manner, the CREs, R34A03, R32H10, and R33F06 govern the Sema-1a expression required for the axon guidance function of Sema-1a during embryonic neural development.

• Journal of Communications and Networks
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• v.6 no.1
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• pp.9-18
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• 2004

Self-encoded multiple access (SEMA) is a unique realization of random spread spectrum. As the term implies, the spreading code is obtained from the random digital information source instead of the traditional pseudo noise (PN) code generators. The time-varying random codes can provide additional security in wireless communications. Multi-rate transmissions or multi-level grade of services are also easily implementable in SEMA. In this paper, we analyze the performance of SEMA in additive white Gaussian noise (AWGN) channels and Rayleigh fading channels. Differential encoding eliminates the BER effect of error propagations due to receiver detection errors. The performance of SEMA approaches the random spread spectrum discussed in literature at high signal to noise ratios. For performance improvement, we employ multiuser detection and Turbo coding. We consider a downlink synchronous system such as base station to mobile communication though the analysis can be extended to uplink communications.

• BMB Reports
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• v.56 no.3
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• pp.160-165
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• 2023

Vascular calcification is common in cardiovascular diseases including atherosclerosis, and is associated with an increased risk of pathological events and mortality. Some semaphorin family members play an important role in atherosclerosis. In the present study, we show that Semaphorin 4D/Sema4D and its Plexin-B1 receptor were significantly upregulated in calcified aorta of a rat chronic kidney disease model. Significantly higher Sema4D and Plexin-B1 expression was also observed during inorganic phosphate-induced calcification of vascular smooth muscle cells. Knockdown of Sema4D or Plexin-B1 genes attenuated both the phosphate-induced osteogenic phenotype of vascular smooth muscle cells, through regulation of SMAD1/5 signaling, as well as apoptosis of vascular smooth muscle cells, through modulation of the Gas6/Axl/Akt survival pathway. Taken together, our results offer new insights on the role of Sema4D and Plexin-B1 as potential therapeutic targets against vascular calcification.

• Journal of Communications and Networks
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• v.9 no.1
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• pp.50-55
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• 2007

We propose to apply chip interleaving and iterative detection to self-encoded multiple access (SEMA) communications. In SEMA, the spreading code is obtained from user bit information itself without using a pseudo noise code generator. The proposed scheme exploits the inherent diversity in self encoded spread spectrum signals. Chip interleaving not only increases the diversity gain, but also enhances the performance of iterative detection. We employ user-mask and interference cancellation to decouple self-encoded multiuser signals. This paper describes the proposed scheme and analyzes its performance. The analytical and simulation results show that the proposed system can achieve a 3 dB power gain and possess a diversity gain that can yield a significant performance improvement in both Rayleigh and multipath fading channels.

• Proceedings of the Korea Institutes of Information Security and Cryptology Conference
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• 2006.06a
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• pp.148-152
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• 2006

스마트카드에 대한 전자파 분석 공격은 스마트카드 내의 마이크로프로세서가 연산될 때, 방사하는 의도되지 않은 전자파를 수집하여 비밀정보를 알아내는 공격이다. 이 경우에는 스마트카드에 어떤 훼손도 가하지 않고 비밀정보를 알아낼 수 있어, 기존에 국내외적으로 활발히 연구된 전력 분석 공격보다 더욱 현실적이고, 강력한 공격이다. 본 논문은 국내에서는 처음으로 스마트카드에 대한 전자파 분석 공격인 SEMA와 DEMA 공격 실험을 하였다. 그 결과 공개키 알고리즘인 RSA에 SEMA 공격을 성공하였고, 이에 대한 방어대책을 적용하여 방어를 하였다. 그리고, 국내 표준 블록 암호 알고리즘인 ARIA에 DEMA 공격을 적용하여, 비밀키를 알아냈다.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.11
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• pp.5879-5882
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• 2012

Breast cancer is the leading cause of cancer deaths among women worldwide, including Thailand. In the present study, the differential mRNA expression of SVEP1, LPHN3, KLB, ITGA7, SEMA3G, TNS1 and MMP13 genes was examined in breast cancer using quantitative real-time reverse transcription polymerase chain reaction (QRT-PCR). Among these genes, increased LPHN3 and MMP13 mRNA expression levels correlated with axillary-node metastasis (P=0.02). Multiple logistic regression analysis revealed that LPHN3 and MMP13 mRNA expression is significantly associated with axillary node status in breast cancer (P=0.04).

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.3B
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• pp.175-182
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• 2006

In this paper, we propose a Localized Adaptive QoS Routing Scheme using POMDP and Exploration Bonus Techniques. Also, this paper shows that CEA technique using expectation values can be simply POMDP problem, because performing dynamic programming to solve a POMDP is highly computationally expensive. And we use Exploration Bonus to search detour path better than current path. For this, we proposed the algorithm(SEMA) to search multiple path. Expecially, we evaluate performances of service success rate and average hop count with $\phi$ and k performance parameters, which is defined as exploration count and intervals. As result, we knew that the larger $\phi$, the better detour path search. And increasing n increased the amount of exploration.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.24
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• pp.10993-10993
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• 2015