• Title/Summary/Keyword: MP4

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The Effect of Hydrophobicity and Amphiphilicity on the Mastoparan B-induced Antibacterial Activity and Hemolytic Activity (Mastoparan B의 항균 활성 및 용혈 작용에 미치는 소수성도와 양친매성의 영향)

  • Lee, Bong-Hun;Kim, Kwang-Ho;Jang, Tae-Sik;Park, Nam-Kyu;Park, Jang-Su;Kang, Shin-Won
    • Korean Journal of Microbiology
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    • v.34 no.1_2
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    • pp.26-30
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    • 1998
  • Tetradecapeptide, Mastoparan B(MP B) and its [$Ala^2$]-, [$Ala^4$]-, [$Ala^6$]-, [$Ala^9$]-MP B derivatives were synthesized, and then their antibacterial and hemolytic activities were assayed to examine the effect of hydrophobicity and amphiphilicity on the MP B-induced those activities. MP B and more hydrophobic [$Ala^2$]-, [$Ala^4$]-MP B showed stronger antibacterial activity and less hydrophobic [$Ala^6$]-MP B than MP B did similar or weaker activity, so more hydrophobic [Ala]-MP B derivative had stronger activity. But more hydrophobic [$Ala^9$]-MP B than MP B showed weaker activity because of its Trp substitution by Ala. On the other hand, [$Ala^2$]- and [$Ala^4$]-MP B showed 100.0% and 69.4% hemolytic activity, but [$Ala^6$]-MP B did the weakest activity(6.1%) and [$Ala^9$]-MP B, weaker activity(26.0%) than MP-B. Therefore, more hydrophobic [Ala]-MP B derivative had stronger activity and the effect of amphiphilicity on the activity was weak.

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Synthesis and Thermal Degradation of Poly(oxydiethylene adipate urethane) Composites Containing Cloisite 30B and Melamine Phosphate (Cloisite 30B와 멜라민포스페이트를 함유한 Poly(oxydiethylene adipate urethane) Composites의 합성과 열분해 특성)

  • Shin, Seung-Wook;Lee, Sang-Ho
    • Polymer(Korea)
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    • v.36 no.5
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    • pp.643-650
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    • 2012
  • In order to improve the thermal stability of polyurethane, we synthesized poly(adipate urethane) (PAU) and three PAU composites, PAU/30B (2.7 wt% 30B), PAU/MP (2.2 wt% MP), PAU/30B/MP (2.2 wt% 30B and 2.2 wt% MP), from poly(oxydiethylene adipate)-diol (PAD), 4,4'-methylene diphenyl diisocyanate (MDI), Cloisite 30B (30B), and melamine phosphate (MP). 30B and MP were introduced into the reactant mixture at the initial stage of the esterification between adipic acid and diethylene glycol, so 30B and MP were evenly dispersed in the PAU composites for long period. At temperatures lower than $250^{\circ}C$, the PAU composites were degraded faster than pristine PAU, mainly due to the decomposition of 30B and MP. At higher temperatures, the 30B and MP enhanced the thermal stability of the PAU composites. Compared with the pristine PAU, the thermal decomposition rates of the PAU composites decreased by 13~17%. In air, the residual weights of PAU/30B, PAU/MP, and PAU/30B/MP were 2.4, 2.3, and 7.3 wt% at $700^{\circ}C$, respectively.

Effects of 4MP Doping on the Performance and Environmental Stability of ALD Grown ZnO Thin Film Transistor

  • Kalode, Pranav Y.;Sung, M.M.
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.471-471
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    • 2013
  • Highly stable and high performance amorphous oxide semiconductor thin film transistors (TFTs) were fabricated using 4-mercaptophenol (4MP) doped ZnO by atomic layer deposition (ALD). The 4 MP concentration in ZnO films were varied from 1.7% to 5.6% by controlling Zn: 4MP pulses. The carrier concentrations in ZnO thin films were controlled from $1.017{\times}10^{20}$/$cm^3$ to $2,903{\times}10^{14}$/$cm^3$ with appropriate amount of 4MP doping. The 4.8% 4MP doped ZnO TFT revealed good device mobility performance of $8.4cm^2V-1s-1$ and on/off current ratio of $10^6$. Such 4MP doped ZnO TFTs were stable under ambient conditions for 12 months without any apparent degradation in their electrical properties. Our result suggests that 4 MP doping can be useful technique to produce more reliable oxide semiconductor TFT.

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A STUDY ON RELATONS BETWEEN FACIAL SKELETAL PATTERNS AND DENTAL OCCLUSION (안골격형과 교합과의 상호관계에 대한 연구)

  • Chang, Young-Il
    • The korean journal of orthodontics
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    • v.12 no.1
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    • pp.21-26
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    • 1982
  • This study was undertaken to document relations between facial skeletal pattern and dental occlusion. The data in .this study were collected from pretreatment cephalometric radiographs and study models of patients' records present in the files of Orthodontic Department, Seoul National University Hospital. Patients were selected on the basis of a mandibular plane-sella nasion angle equal to or greater than $38^{\circ}$ (high SN-MP angle) or equal to or less than $26^{\circ}$ (low SN-MP angle). Patients in the mixed dentition and with missing permanent teeth were excluded for ease of assessing tooth size / arch circumference relationships and then 30 high SN-MP and 11 low SN-MP patients were selected among them. The mean age of these two groups of patients was high SN-MP, $12.8{\pm}1.23$ years and low SN-MP, $13.0{\pm}1.48$ years. The following conclusions were obtained. 1. In the maxilla and mandible the mean tooth size of high SN-MP patients was nearlly identical to the low SN-MP patients. 2. The mean maxillary arch circumference was increased in low SN-MP group compared with high SN-MP group and a smilar, but smaller, mean increase was present in mandible. 3. The difference between the mean maxillary circumference required and the mean maillary circumference present ranged from -4.8mm in the high SN-MP group to -1.3mm in the low SN-MP group. A small range of means occurred in the mandible (high SN-MP: -4.0mm to low SN-MP: -1.8mm). 4. In the maxilla and mandible the mean arch length was nearly identical in the high and low SN-MP groups. 5. The mean incisor inclination was increased as the SN-MP angle decreased in the maxilla and mandible. 6. The men distance of the maxillary first molar from anterior border of the pterygomaxillary fissure was nearly similar between high and low groups. 7. The mean mandibular intermolar width was increased from high SN-MP to low SN-MP patients.

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Studies on the Sedative Alkaloids from Zizyphus spinosus Semen

  • Han, Byung-Hoon;Park, Myung-Hwan;Park, Jeong-Hill
    • Korean Journal of Pharmacognosy
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    • v.16 no.4
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    • pp.233-238
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    • 1985
  • A number of sedative alkaloids were isolated from Sanjoin(酸棗仁), the seeds of Zizyphus vulgaris Lamark var. spinosus Bunge (Rhamnaceae) which is an important Chinese medicinal material used to treat insomnia and sometimes to treat sleepiness. Those compounds were designated as Sanjoinine-A, B, C, D, etc. depending on the order of increasing polarity. Sanjoinine-A, $C_{31}H_{42}N_4O_4$, $mp\;249^{\circ}$, $[{\alpha}]^{27}_D-316$, Sanjoinine-B, $C_{30}H_{40}N_4O_4$, $mp\;212{\sim}4^{\circ}$, Sanjoinene, $C_{29}H_{35}N_3O_4$, $mp\;281{\sim}2^{\circ}$, $[{\alpha}]^{22}_D-272$, Sanjoinine-D, $C_{32}H_{46}N_4O_5$, $mp\;256{\sim}8^{\circ}$, $[{\alpha}]^{22}_D-53.6$, Sanjoinine-F, $C_{31}H_{42}N_4O_5$, $mp\;228{\sim}9^{\circ}$, $[{\alpha}]^{22}_D-215$, and $Sanjoinine-G_1,\;C_{31}H_{44}N_4O_5,\;mp\;236{\sim}8^{\circ},\;[{\alpha}]^{22}_D-68.6$, were found as 14-membered cyclic peptide alkaloids, $Sanjoinine-G_2,\;C_{30}H_{42}N_4O_4,\;mp\;182^{\circ},\;[{\alpha}]^{22}_D-79.2$, as being open chain peptide alkaloid, and Sanjoinine-E, $C_{19}H_{21}NO_2$, $mp\;166^{\circ}$, $[{\alpha}]^{20}_D-146.2$, N-Methylasimilobine, $C_{18}H_{19}NO_2$, $mp\;193{\sim}5^{\circ}$, $[{\alpha}]^{20}_D-204$, Sanjoinine-Ia, $C_{18}H_{19}NO_2$, $mp\;155{\sim}7^{\circ}$, $[{\alpha}]^{20}_D-140$, Sanjoinine-Ib, $C_{19}H_{21}NO_4$, $mp\;184^{\circ}$, Sanjoinine-K, $C_{16}H_{19}NO_3$, $mp\;159{\sim}61^{\circ}$, $[{\alpha}]^{20}_D+35$, Caaverine, $C_{17}H_{17}NO_2$, $mp\;204^{\circ}$, $[{\alpha}]^{20}_D-80$, and Zizyphusine, $C_{20}H_{24}NO_4$, $mp\;214{\sim}6^{\circ}$, $[{\alpha}]^{20}_D+317$ as being aporphine alkaloids. The heat treatment of the cyclic peptide alkaloids produced their isomeric products which showed enhanced sedative activity. The chemical structure of the isomeric products will be discussed.

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Controlling Electrical Properties in Zinc Oxide Thin Films by Organic Concentration

  • Yun, Gwan-Hyeok;Han, Gyu-Seok;Jeong, Jin-Won;Seong, Myeong-Mo
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.08a
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    • pp.209.2-209.2
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    • 2013
  • We proposed and fabricated zinc oxide thin-film transistors (TFTs) employing 4-mercaptophenol (4MP) doped ZnO by atomic layer deposition (ALD) that results in highly stable and high performance. The 4MP concentration in ZnO films were varied from 1.7% to 5.6% by controlling Zn:4MP pulses. The n-type carrier concentrations in ZnO thin films were controlled from $1.017{\times}10^{20}/cm^3$ to $2.903{\times}10^{17}/cm^3$ with appropriate amount of 4MP doping. The 4.8% 4MP doped ZnO TFT revealed good device mobility performance of 8.4 $cm^2/Vs$ and the on/off current ratio of 106. Such 4MP doped ZnO TFTs exhibited relatively good stability (${\Delta}V_{th}$: 2.4 V) under positive bias-temperature stress while the TFTs with only ZnO showed a 4.3 ${\Delta}V_{th}$ shift, respectively.

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A Direction of Emotion Design for Future MP3 Players by Trend Analysis (추세분석을 통한 미래 MP3 플레이어의 감성디자인 방향 모색)

  • Lee, Yu-Ri;Yang, Jong-Youl
    • Science of Emotion and Sensibility
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    • v.10 no.4
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    • pp.511-521
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    • 2007
  • It is very important that design based on preference of consumers who continuously change. Therefore, the method that can decide on the design concept which a consumer can prefer in future points of time that a design is released is necessary. There may be various ways to decide a design concept, but trend analysis is one of the best ways to be able to satisfy consumer preference. The purpose of this study is to provide a process that can give a direction of MP3 player design oriented consumer emotion. For the purpose, we considered about trend analysis as the ways that can present the design direction that can grasp a change of continuous preference, and a consumer can prefer with early bases in future points of time of a consumer. In this empirical research, we decided on design elements and levels of the elements after collecting 228 MP3 players released from 2000 to 2007, and carried out trend analysis through homogeneity analysis by SPSS program. In the result, we knew that future consumers also will regard emotional experience consumption as important. So, MP3 player design will be developed into consumer emotion-oriented design. We predict 4 trends for a future MP3 player design. 1. Development of high-priced MP3 player with various multimedia functions. 2. Development of MP3 player with basic functions. 3. Development of new convergence products with MP3 function. 4. Development of new MP3 player based on flash memory. If designers can infer a future MP3 player design from this design trend results, the probability that can occupy competitive advantage in their competitions will be high. Therefore this study can be useful.

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Synthesis of Melamine Phosphate-Polyurethane Composite Foam Blown by Water and Characterization of Its Thermal Properties (H2O로 발포된 멜라민포스페이트-폴리우레탄폼 복합체 합성과 열적 특성 분석)

  • Park, Kyeong-Kyu;Lee, Sang-Ho
    • Polymer(Korea)
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    • v.38 no.4
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    • pp.441-448
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    • 2014
  • Polyurethane/melamine phosphate composite foam (MP-PUF) was prepared from poly(adipate)diol/melamine phosphate composite (f=2), polyether-polyol (f=4.6), and PMDI (f=2.5). The thermal properties of MP-PUF such as morphology, closed-cell content, thermal conductivity, and thermal stabilities were characterized. Water was used as a blowing agent, and the composition of melamine phosphate (MP) was maintained at $1.43{\pm}0.3wt%$ of MP-PUF. As the content of water increased, the thermal conductivity of pure polyurethane foam (PUF) decreased, whereas the thermal conductivity of MP-PUF increased. The thermal stabilities of the PUF and the MP-PUF were maximized at 5 php $H_2O$, and then decreased at the higher $H_2O$ contents. The thermal stabilities of MP-PUF were greatly enhanced due to the synergetic effect of MP and urea, which was generated during the blowing process. The temperature of 50% residual mass of MP-PUF increased to $370{\sim}450^{\circ}C$ and the temperature of 30% residual mass exceeded over $700^{\circ}C$. Compared to the PUF, the temperature of 50% residual mass and 30% residual mass were higher than 25 and $70^{\circ}C$, respectively.

Skeletal Age Assessment of SMI and MP3 Stages to Predict the Pubertal Growth Spurt (사춘기 최대 성장 단계 예측을 위한 SMI 및 MP3 단계별 골연령 평가)

  • Lee, Yeonju;Mah, Yonjoo
    • Journal of the korean academy of Pediatric Dentistry
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    • v.46 no.3
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    • pp.233-238
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    • 2019
  • This study aimed to assess the skeletal age of skeletal maturational indicator (SMI) and middle phalanx of the middle finger (MP3) stages and to predict the SMI and MP3 stages corresponding to pubertal growth spurt in boys and girls respectively. The skeletal age was assessed from hand-wrist radiographs of 363 children (182 boys, 181 girls) aged 7 to 16 years by radiologists using the Korean standard bone age chart. Also, SMI and MP3 stages were evaluated from the radiographs. From these records, the mean skeletal age of SMI and MP3 stages was calculated. The stages including pubertal growth spurt were SMI 4 - 5, MP3 FG - G stages in boys and SMI 3 - 4, MP3 F - FG stages in girls.

Implementation and Translation of Major OpenMP Directives for Chip Multiprocessor without using OS (단일 칩 다중 프로세서상에서 운영체제를 사용하지 않은 OpenMP 구현 및 주요 디렉티브 변환)

  • Jeun, Woo-Chul;Ha, Soon-Hoi
    • Journal of KIISE:Computer Systems and Theory
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    • v.34 no.4
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    • pp.145-157
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    • 2007
  • OpenMP is an attractive parallel programming model for a chip multiprocessor because there is no standard parallel programming method for a chip multiprocessor and it is easy to write a parallel program in OpenMP. Then, chip multiprocessor systems can have various architectures according to target application programs. So, we need to implement OpenMP in different way for each system. In this paper, we propose the implementation and the effective translation of major OpenMP directives for a chip multiprocessor without using OS to improve the performance without using special hardware and without extending the OpenMP directives. We present the experimental results on our target platform CT3400.