• Title/Summary/Keyword: Par-4

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Dry Etching Properties of PAR (poly-arylate) Substrate for Flexible Display Application (플렉시블 디스플레이 응용을 위한 폴리아릴레이트 기판의 식각 특성)

  • Hwanga, Jin-Ho
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.29 no.12
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    • pp.824-828
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    • 2016
  • In this study, effects of ICP (inductively coupled plasma) treatment on PAR thin film have been investigated. A maximum etch rate of the PAR thin films and the selectivity of PAR to PR were obtained as 110 nm/minand 1.1 in the $CF_4/O_2$ (5:15 sccm) gas mixture. We present the surface properties of PAR thin film with various treatment conditions. The surface morphology and cross section of the PAR thin film was observed by AFM (atomic force microscopy) and FE-SEM (filed emission scanning electron microscopy).

Polyarylate-Nylon 6 Block Copolymers : Synthesis and Its Miscibility in Binary Blends with Polyarylate or Nylon 6 Homopolymer (폴리아릴레이트-나일론 6 블록공중합체 : 합성 및 폴리아릴레이트 혹은 나일론 6 단일중합체와의 상용성)

  • Ahn, Tae-Oan;Lee, Suk-Min;Jeong, Han-Mo;Lee, Sang-Won
    • Applied Chemistry for Engineering
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    • v.4 no.2
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    • pp.349-357
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    • 1993
  • Polyarylate(PAR)-nylon 6 block copolymers of various block lengths were prepared by the anionic polymerization of ${\varepsilon}$-caprolactam using the polymeric activator from hydroxy-difuncrtional PAR and toluene diisocyanate. Phase separated morphology of PAR-nylon 6 block copolymer was suggerted from the thermal properties measured by differential scanning calorometry(d.s.c.). Partial miscbility between PAR block and nylon 6 block of the block copolymers was more evident at shorter length of constituent blocks. In binary blends of PAR-nylon 6 block copolymer with PAR or nylon 6 homopolymer, molecular-level mixing of homopolymers with corresponding blocks of block copolymer was supposed from the thermal properties measured by d.s.c..

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Down-regulation of Protease-activated Receptor 4 in Lung Adenocarcinoma is Associated with a More Aggressive Phenotype

  • Jiang, Ping;Yu, Guo-Yu;Zhang, Yong;Xiang, Yang;Hua, Hai-Rong;Bian, Li;Wang, Chun-Yan;Lee, Wen-Hui;Zhang, Yun
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.6
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    • pp.3793-3798
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    • 2013
  • The role of protease-activated receptors (PARs) in lung tumors is controversial. Although PAR4 is preferentially expressed in human lung tissues, its possible significance in lung cancer has not been defined. The studies reported herein used a combination of clinical observations and molecular methods. Surgically resected lung adenocarcinomas and associated adjacent normal lung tissues were collected and BEAS-2B and NCI-H157 cell lines were grown in tissue culture. PAR4 expression was evaluated by RT-PCR, RT-qPCR, Western blotting and immunohistochemistry analysis. The results showed that PAR4 mRNA expression was generally decreased in lung adenocarcinoma tissues as compared with matched noncancerous tissues (67.7%) and was associated with poor differentiation (p=0.017) and metastasis (p=0.04). Western blotting and immunohistochemical analysis also showed that PAR4 protein levels were mostly decreased in lung adenocarcinoma tissues (61.3%), and were also associated with poor differentiation (p=0.035) and clinical stage (p=0.027). Moreover, PAR4 expression was decreased in NCI-H157 cells as compared with BEAS-2B cells. In conclusion, PAR4 expression is significantly decreased in lung adenocarcinoma, and down-regulation of PAR4 is associated with a more clinically aggressive phenotype. PAR4 may acts as a tumor suppressor in lung adenocarcinoma.

The Ligand Occupancy of Endothelial Protein C Receptor Switches the Signaling Specificity of Thrombin from a Disruptive to a Protective Response in Endothelial Cells

  • Bae, Jong-Sup;Kim, Yong-Ung;Park, Moon-Ki
    • Proceedings of the Korean Environmental Sciences Society Conference
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    • 2008.11a
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    • pp.538-544
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    • 2008
  • Activated protein C (APC) is thought to exert antiinflammatory activities through the endothelial protein C receptor (EPCR)-dependent cleavage of protease activated receptor 1 (PAR-1) in endothelial cells. Since thrombin cleaves PAR-1 with $\sim$3-4-orders of magnitude higher efficiency, and PAR-1 is a target for proinflammatory activities of thrombin, it is not understood how APC can elicit protective responses through the cleavage of PAR-1. In this study, we demonstrate that EPCR is associated with caveolin-1 in endothelial lipid rafts, but its occupancy by protein C leads to its dissociation from caveolin-1 and subsequent recruitment of PAR-1 to protective signaling pathways through the coupling of PAR-1 to Gi-protein. When EPCR is bound by protein C, the PAR-1-dependent protective response in endothelial cells can be mediated by either thrombin or APC. These results provide a new paradigm for understanding the mechanism through which PAR-1 and EPCR participate in cellular signaling events in endothelial cells.

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Evaluation of orthodontic treatment outcomes and post-treatment changes by the PAR index (PAR 지수를 이용한 교정치료 결과의 평가에 관한 연구)

  • Cheong, Soo-Bong;Park, Young-Guk
    • The korean journal of orthodontics
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    • v.31 no.4 s.87
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    • pp.393-401
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    • 2001
  • The purposes of this study were to assess the treatment results in orthodontic department, Kyung Hee University, to evaluate the occlusion at 2 year follow-up control, in relation to the original malocclusion, and changes occurring in the follow-up period, and to determine whether treatment and posttreatment changes of the PAR index were related to the original Angle classification Dental study casts of 25 patients in permanent dentition were evaluated using Peer Assessment Rating (PAR) index. The PAR index was measured at the pretreatment stage, immediately after treatment, and at 2 yews posttreatment. The following results were obtained : 1. The treatment reduced the PAR index by 85.05% and it indicates that KHDC clinic has a high standard of treatment 2. The follow-up result of 75.40% PAR score reduction implies a gain of 9.55% of posttreatment PAR score during follow-up period. 3. There is no relationship between the treatment changes of the PAR index and the orignal Angle classification.

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Adaptive Channel Attenuation Compensation Scheme for Minimum PAR in Satellite OFDMA Downlink (위성 OFDMA Downlink에서 PAR을 최소화 하기 위한 사용자 부채널 할당 및 채널 보상 기법)

  • Kim, Han-Nah;Choi, Kwon-Hue;Ahn, Do-Seob;Kang, Kun-Seok;Kim, Hee-Wook
    • Journal of Satellite, Information and Communications
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    • v.4 no.1
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    • pp.28-35
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    • 2009
  • We investigate the adaptive channel attenuation compensation of satellite OFDMA downlink users for minimum PAR (Peak to Average power Ratio), which is one of the main challenging issues in satellite OFDMA application. First, we analyze and compare PAR performances of two main different channel attenuation compensation schemes for OFDMA, i.e., PC-OFDMA (power control OFDMA) and AMC-OFDMA (Adaptive Modulation and Coding). While AMC-OFDMA maintains the constant transmission powers through entire user data subcarriers, PC-OFDMA has non-uniform subcarrier transmission powers because subcarrier powers are separately controlled to compensate each user's sub-channel attenuation. We newly found the fact that non-uniform subcarrier power in PC-OFDMA achieves rather reduced PAR compared to AMC-OFDMA and the amount of reduction becomes larger as the power differences among subcarriers increase. Also, there is an additional PAR reduction in PC-OFDMA by optimizing subcarrier grouping scheme for user's sub-channelization.

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TopoisomeraseII and Topoisomerase IV Gene Mutations Fluoroquinolone Resistance of Pseudomonas aeruginosa

  • Kim Yuntae;Baik Heongseok
    • Biomedical Science Letters
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    • v.10 no.4
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    • pp.507-514
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    • 2004
  • The Pseudomonas aeruginosa isolated from the clinical specimens has a mutation on the QRDR (quinolone resistance determining region). There were obvious mutations in both gyrA and parC gene which are major targets of quinolone. Simultaneous mutations were found two sites or more on these genes in all of ten strains. GyrB or parE gene had only silent mutation without converted amino acids. We confirmed that P. aeruginosa from clinical specimens exhibited decreased sensitivity to fluroquiolone due to changed Thr-83→lle and Asp-87→Asn types on gyrA and altered Ser-87→Leu type on parC. This is the first finding that a new Met-93→Thr type on parC as well as mutations on gyrB or parE genes differed from existing patterns. This study showed more mutations of gyrA rather than parC, suggesting that change of Type Ⅳ topoisomerase is more serious than that of type Ⅱ (DNA gyrase).

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Implementation of Parallel Volume Rendering Using the Sequential Shear-Warp Algorithm (순차 Shear-Warp 알고리즘을 이용한 병렬볼륨렌더링의 구현)

  • Kim, Eung-Kon
    • The Transactions of the Korea Information Processing Society
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    • v.5 no.6
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    • pp.1620-1632
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    • 1998
  • This paper presents a fast parallel algorithm for volume rendering and its implementation using C language and MPI MasPar Programming Language) on the 4,096 processor MasPar MP-2 machine. This parallel algorithm is a parallelization hased on the Lacroute' s sequential shear - warp algorithm currently acknowledged to be the fastest sequential volume rendering algorithm. This algorithm reduces communication overheads by using the sheared space partition scheme and the load balancing technique using load estimates from the previous iteration, and the number of voxels to be processed by using the run-length encoded volume data structure.Actual performance is 3 to 4 frames/second on the human hrain scan dataset of $128\times128\times128$ voxels. Because of the scalability of this algorithm, performance of ]2-16 frames/sc.'cond is expected on the 16,384 processor MasPar MP-2 machine. It is expected that implementation on more current SIMD or MIMD architectures would provide 3O~60 frames/second on large volumes.

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Estimation of the PAR Irradiance Ratio and Its Variability under Clear-sky Conditions at Ieodo in the East China Sea

  • Byun, Do-Seong;Cho, Yang-Ki
    • Ocean Science Journal
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    • v.41 no.4
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    • pp.235-244
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    • 2006
  • Determining 'photosynthetically active radiation' (PAR) is a key part of calculating phytoplankton productivity in a biogeochemical model. We explore the daily and seasonal variability in the ratio of PAR irradiance to total irradiance that occurred at Ieodo Ocean Research Station (IORS) in the East China Sea under clear-sky conditions in 2004 using a simple radiative transfer model (RTM). Meteorological data observed at IORS and aerosol optical properties derived from Aerosol Robotic Network observations at Gosan are used for the RTM. Preliminary results suggest that the use of simple PAR irradiance-ratio values is appropriate in calculating phytoplankton productivity as follows: an average of $0.44\;({\pm}0.01)$ in January to an average of $0.48\;({\pm}0.01)$ in July, with average daily variabilities over these periods of about $0.016\;({\pm}0.008)$ and $0.025\;({\pm}0.008)$, respectively. The model experiments demonstrate that variations in the major controlling input parameters (i.e. solar zenith angle, precipitable water vapor and aerosol optical thickness) cause PAR irradiance ratio variation at daily and seasonal timescales. Further, increases (>0.012) in the PAR irradiance ratio just below the sea-surface are positively correlated with high solar zenith angles and strong wind stresses relative to those just above the sea-surface.

A Parallel Algorithm for Merging Heaps on MasPar Machine (MasPar 머쉰상의 병렬 힙 병합 알고리즘)

  • Min, Yong-Sik
    • The Transactions of the Korea Information Processing Society
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    • v.2 no.4
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    • pp.554-560
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    • 1995
  • In this paper, we suggest a parallel algorithm to merge priority queues organized in two heaps, kheap and nheap of sizes k and n, correspondingly. Employing max(2$^{-1}$, $\ulcorner$(m+1)/4$\lrcorner$'s processors, this algorithm requires O(log(n/k)*log(n)) on an EREW-PRAM, where i is the height of the heap and m is the summation of sizes n and k. Also, when we run it on the MasPar machine, this method achieves a 33.934-fold speedup with 64 processors to merge 8 million data items which consist of two heaps of different sizes. So our parallel algorithm's EPU is close to 1, which is considered as an optimal speedup ratio.eedup ratio.

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