• 제목/요약/키워드: $^{16}N$

검색결과 8,472건 처리시간 0.039초

Expression of c-Jun in pancreatic islet $\alpha$-cells of nonobese diabetic(NOD) mice

  • Park, Sang-Joon;Lee, Sae-Bom;Choi, Yang-Kyu;Lee, Chul-Ho;Hyun, Byung-Hwa;Lee, Keun-Joa;Ryu, Si-Yun;Cho, Sung-Whan;Song, Jae-Chan;Lee, Cha-Soo;Jeong, Kyu-Shik
    • 한국수의병리학회지
    • /
    • 제2권1호
    • /
    • pp.17-24
    • /
    • 1998
  • This is the first report of c-Jun protein expression and mRNA in a pancreatic islet in a nonobese diabetic(NOD) state mice. In this experiment NOD mice with insulin-dependent diabetes mellitus type I at age 16 weeks(n=7) just before death(n=4) were used. The control group consist of prediabetic NOD(8 weeks n=7) and ICR(8 weeks n=7 and 16 weeks n=7) mice. c-Jun positive cells in the pancreatic islet of NOD mice were localized in the same positions as a-glucagon producing cells. immunoreactivity was negative in the prediabetic NOD(8 weeks) and ICR(8 weeks and 16 weeks) mice. The number of c-Jun positive cells in mice with severe diabetic state just before death were significantly decreased when compared to NOD(16 weeks) mice. Expression of c-Jun in mRNA level was assessed by RT-PCR method. The levels of mRNA in NOD(16 weeks) mice group were elevated in total pancreatic tissues. The present results suggest that the induction of proto-oncogene protein may be of significance in assessing cell specific injury and may play a functional role between pancretic islet $\alpha$-cells and $\beta$-cells in the diabetic state.

  • PDF

Effects of neutron irradiation on superconducting critical temperatures of in situ processed MgB2 superconductors

  • Kim, C.J.;Park, S.D.;Jun, B.H.;Kim, B.G.;Choo, K.N.;Ri, H.C.
    • 한국초전도ㆍ저온공학회논문지
    • /
    • 제16권1호
    • /
    • pp.9-13
    • /
    • 2014
  • Effects of neutron irradiation on the superconducting properties of the undoped $MgB_2$ and the carbon(C)-doped $MgB_2$ bulk superconductors, prepared by an in situ reaction process using Mg and B powder, were investigated. The prepared $MgB_2$ samples were neutron-irradiated at the neutron fluence of $10^{16}-10^{18}n/cm^2$ in a Hanaro nuclear reactor of KAERI involving both fast and thermal neutron. The magnetic moment-temperature (M-T) and magnetization-magnetic field (M-H) curves before/after irradiation were obtained using magnetic property measurement system (MPMS). The superconducting critical temperature ($T_c$) and transition width were estimated from the M-T curves and critical current density ($J_c$) was estimated from the M-H curves using a Bean's critical model. The $T_cs$ of the undoped $MgB_2$ and C-doped $MgB_2$ before irradiation were 36.9-37.0 K and 36.6-36.8 K, respectively. The $T_cs$ decreased to 33.2 K and 31.6 K, respectively after irradiation at neutron fluence of $7.16{\times}10^{17}n/cm^2$, and decreased to 22.6 K and 24.0 K, respectively, at $3.13{\times}10^{18}n/cm^2$. The $J_c$ cross-over was observed at the high magnetic field of 5.2 T for the undoped $MgB_2$ irradiated at $7.16{\times}10^{17}n/cm^2$. The $T_c$ and $J_c$ variation after the neutron irradiation at various neutron fluences were explained in terms of the defect formation in the superconducting matrix by neutron irradiation.

왜매치, Abbottina springeri(Cypriniformes: Cyprinidae)의 난발생 및 자치어 형태발달 (Morphological Development of Eggs, Larvae and Juveniles of the Abbottina springeri (Cypriniformes: Cyprinidae))

  • 박재민;유동재;조성장;한경호
    • 한국어류학회지
    • /
    • 제33권3호
    • /
    • pp.167-176
    • /
    • 2021
  • 본 연구는 왜매치의 초기생활사를 밝히기 위해 충청남도 당진시 서원천에서 성어를 채집하여 인공수정을 통해 수행하였다. 왜매치 암컷의 산란량은 1,225~2,100개(1,662±437개, n=10) 정도였다. 난의 형태는 원형으로 크기는 1.05~1.13(1.08±0.02, n=30) mm였다. 수정란은 수온 22℃에서 부화까지 72~80시간이 소요되었다. 부화 직후의 난황자어는 전장 2.10~2.23 (2.16±0.04, n =10) mm로 입과 항문은 열려 있지 않았고 난황을 가지고 있었다. 부화 후 5일째는 전장 3.29~3.45 (3.36±0.04, n=10) mm로 난황을 모두 흡수하였고 먹이를 섭취하면서 전기자어로 이행하였다. 부화 후 15일째는 전장 4.97~5.30 (5.13±0.12, n=10) mm로 척추 끝부분이 상단으로 휘어지기 시작하면서 중기자어로 이행하였다. 부화 후 25일째는 전장 8.97~9.60 (9.44±0.16, n=10) mm로 꼬리지느러미 말단 끝부분이 45°로 완전히 휘어지면서 후기자어로 이행하였다. 부화 후 35일째는 전장 12.0~13.5 (12.7±0.53, n=10) mm로 각 부위별 지느러미 기조 수(등지느러미 iii 7개, 뒷지느러미 iii 6개, 배지느러미 i 7개)가 정수로 도달하면서 치어기로 이행하였다.

부착율 개선을 위해 증발 법으로 제작한 Bi2Sr2CanCun+1Ox 박막의 부착 특성 (Sticking Characteristics in Bi2Sr2CanCun+1Ox Thin Films Fabricated by using the Evaporation Method to Improve the Sticking Ratio)

  • 천민우;박용필
    • 한국전기전자재료학회논문지
    • /
    • 제16권11호
    • /
    • pp.1029-1034
    • /
    • 2003
  • The Bi$_2$Sr$_2$Ca$_{n}$Cu$_{n+1}$ O$_{x}$, superconducting thin films arc fabricated by using the sputtering and evaporation method. Because we confirmed the sticking ratio of Bi element in the Bi$_2$Sr$_2$Ca$_{n}$Cu$_{n+1}$ O$_{x}$ superconducting thin film fabricated by using the sputtering method was much lower than the expected value, to get the enough number of the flakes of Bi, faraday cup was used to evaporate Bi clement. As a result of the fabrication, Bi 2201 and Bi 2212 single phases could be made by the optima of deposition condition. And we confirmed the sticking coefficient of Bi element was clearly related to the temperature change of the substrate and the generation of Bi22l2 phase

3C-SiC 버퍼층위에 증착된 M/NEMS용 다결정 AlN 박막의 특성 (Characteristics of polycrystalline AlN thin films deposited on 3C-SiC buffer layers for M/NEMS applications)

  • 정귀상;이태원
    • 센서학회지
    • /
    • 제16권6호
    • /
    • pp.462-466
    • /
    • 2007
  • Aluminum nitride (AlN) thin films were deposited on Si substrates by using polycrystalline (poly) 3C-SiC buffer layers, in which the AlN film was grown by pulsed reactive magnetron sputtering. Characteristics of grown AlN films were investigated experimentally by means of FE-SEM, X-ray diffraction, and FT-IR, respectively. The columnar structure of AlN thin films was observed by FE-SEM. X-ray diffraction pattern proved that the grown AlN film on 3C-SiC layers had highly (002) orientation with low value of FWHM (${\Theta}=1.3^{\circ}$) in the rocking curve around (002) reflections. These results were shown that almost free residual stress existed in the grown AlN film on 3C-SiC buffer layers from the infrared absorbance spectrum. Therefore, the presented results showed that AlN thin films grown on 3C-SiC buffer layers can be used for various piezoelectric fields and M/NEMS applications.

TiN 박막을 코팅한 드릴의 수명향상에 관한 연구 (A Study on the Life Enhancement of TiN Coated Drill)

  • 김홍우;김문일
    • 대한기계학회논문집
    • /
    • 제16권12호
    • /
    • pp.2340-2348
    • /
    • 1992
  • 본 연구에서는 드릴(SKH9종)에 스퍼터링법으로 Ti 중간층을 약 0.2$\mu\textrm{m}$의 두께 로 코팅한후, 그 위에 플라즈마 화학증착법으로 TiN박막을 코팅한 드릴로 드릴링 시험 을 행하여 수명을 평가하였으며, 드릴의 내마멸성 및 드릴링한 구멍 내면의 조도를 코 팅하지 않은 드릴 및 TiN 코팅한 드릴과 비교하므로서 Ti/TiN코팅처리에 의한 공구성 능 및 수명향상 효과를 평가하고자 하였다.

N,N'-di-tert-butoxycabonyl-2,7-diazabicyclo[3.3.0]oct-4-ene의 결정구조 (Crystal Structure of N,N'-di-tert-butoxycabonyl-2, 7-diazabicyclo[3.3.0]oct-4-ene.)

  • 김문집;이재혁
    • 한국결정학회지
    • /
    • 제8권2호
    • /
    • pp.132-137
    • /
    • 1997
  • N,N'-di-tert-butoxycabonyl-2, 7-diazabicyclo[3.3.0]oct-4-ene의 분자 및 결정구조를 X-선 회절법으로 연구하였다. 이 결정의 분자식은 C16H26N2O4, 결정계는 삼사정계이고 공간군은 P1이다. 단위세포상수 a=11.119(1) Å, b=13.638(1) Å, c=6.214(1) Å이며, α=92.14(1)°, β=103.49(1)°, γ=73.35(1)°, V=877.4(2)Å3, T=293(2)K, Z=2이다. 구조해석에 사용한 X-선은 Cu Kα선(λ=1.5418Å)이다. 구조는 직접법으로 풀었으며, 최소자승법으로 정밀화하였다. 최종 신뢰도 R값은 F0>4σ(F0)인 2389개의 독립회절데이타에 대해 5.38%이였다.

  • PDF

N 도핑된 TiO2 광촉매 박막의 제조 및 특성분석 (Manufacturing and Characterization of N-doped TiO2 Photocatalytic Thin Film)

  • 박상원;남수경;허재은
    • 한국환경과학회지
    • /
    • 제16권6호
    • /
    • pp.683-688
    • /
    • 2007
  • In this study, N doped $TiO_2$ (TiO-N) thin film was prepared by DC magnetron sputtering method to show the photocatalytic activity in a visible range. Various gases (Ar, $O_2\;and\;N_2$) were used and Ti target was impressed by 1.2 kW -5.8 kW power range. The hysteresis of TiO-N thin film as a function of discharge voltage wasn't observed in 1.2 and 2.9kW of applied power. Cross sections and surfaces of thin films by FE-SEM were tiny and dense particle sizes of both films with normal cylindrical structures. XRD pattern of $TiO_2$ and TiO-N thin films was appeared by only anatase peak. Red shift in UV-Vis adsorption spectra was investigated TiO-N thin film. Photoactivity was evaluated by removal rate measurement of suncion yellow among reactive dyes. The photodegradation rate of $TiO_2$ thin film on visible radiation was shown little efficiency but TiO-N was about 18%.

Loss Analysis and Soft-Switching Behavior of Flyback-Forward High Gain DC/DC Converters with a GaN FET

  • Li, Yan;Zheng, Trillion Q.;Zhang, Yajing;Cui, Meiting;Han, Yang;Dou, Wei
    • Journal of Power Electronics
    • /
    • 제16권1호
    • /
    • pp.84-92
    • /
    • 2016
  • Compared with Si MOSFETs, the GaN FET has many advantages in a wide band gap, high saturation drift velocity, high critical breakdown field, etc. This paper compares the electrical properties of GaN FETs and Si MOSFETs. The soft-switching condition and power loss analysis in a flyback-forward high gain DC/DC converter with a GaN FET is presented in detail. In addition, a comparison between GaN diodes and Si diodes is made. Finally, a 200W GaN FET based flyback-forward high gain DC/DC converter is established, and experimental results verify that the GaN FET is superior to the Si MOSFET in terms of switching characteristics and efficiency. They also show that the GaN diode is better than the Si diode when it comes to reverse recovery characteristics.

Melanoma B-16에서 $IL-1{\beta}$ 유발 GnT-III, V 활성에 대한 과루인(瓜蔞仁), 황금(黃芩) 추출물의 영향(影響) (Effects of Trichosanthes kirilowii Maxim and Scutellaria baicalensis Georgi on $IL-1{\beta}-induced$ GnT-III and V in Melanoma B-16)

  • 서운교;정지천
    • 대한한방종양학회지
    • /
    • 제5권1호
    • /
    • pp.103-118
    • /
    • 1999
  • The activity of N-acetylglucosamitnyltransferase(GnT) III and V on a Melanoma B-16 was examined after incubation with interleukin 1 (IL-1). While augumenting cell proliferation, IL-1 resulted in a decrease of GnT-III activity and an increase of GnT-V activities. Consistant with this, Melanoma B-16 cultured with IL-1 showed increased affinlity to Daturam stramonium lectin, which recognizes asialo-tri- and asialeo-tetra-antenery N-linked oligosaccharides. These results indicate that IL-1 modulate glycosyltransferase activity and the oligosaccharide structure of target cells. On the other hand, to investigate whether or not TKM-SG affect GnT-V gene expression in lung metastatic carcinoma, we used RT-PCR methods. TKM-SG treated cell lines showed low levels of secretion of GnT-V mRNA transcription as elucidated by RT-PCR. Thus, with together lower GnT-V activity levels in the medium, TKM-SG was highly effective for lung cancer metastasis treatment and it was concluded that the medicine can be used as a potent anti-lung cancer metastasis medicine.

  • PDF