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Expression of Id-1 Gene in Mouse Uterus (생쥐 자궁에서의 Id-1 유전자의 발현)

  • Nah, Hee-Young;Hong, Seok-Ho;Lee, Ji-Yoon;Chae, Hee-Dong;Kang, Byung-Moon;Kim, Chung-Hoon
    • Clinical and Experimental Reproductive Medicine
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    • v.30 no.2
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    • pp.171-178
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    • 2003
  • 연구 목적: Microarray data에 의해 밝혀진 생쥐자궁에서의 Id 유전자의 hormonal effect와 implantation process 동안의 관계를 조사하고자 실험을 수행하였다. 연구재료 및 방법: 난소절제한 생쥐에 estrogen을 주사하고 6시간, 12시간이 지난 후 자궁을 적출하여 두 가지 방법으로 sample을 준비하였다. 먼저 자궁전체의 RNA를 추출하여 실험하거나 laser capture microdissection (LCM) 방법으로 자궁내막상피세포, 자궁기질세포, 자궁근육층으로 분리하여 RNA를 추출하고 semi-quantative RT-PCR을 수행하여 Id 유전자의 발현을 조사하였다. 임신 4.5일째 생쥐에 Chicago blue dye를 주사하여 착상부위와 비착상부위를 분리하고 RNA를 추출하여 Id 유전자의 발현을 semiquantitative RT-PCR 방법으로 실험하였다. 결 과: Estrogen을 처리한 난소절제된 생쥐 자궁에서의 cDNA microarray 자료에서 Id-1 mRNA는 점진적으로 두 배 이상 증가하였고 Id-2 mNRA는 반대로 시간이 지날수록 두 배 이상 감소하였다. Microarray 자료를 재확인하기 위해 semi-quantitative RT-PCR을 이용하여 실험하였고, 그 결과 Id-1 유전자는 estrogen 처리 6시간까지는 큰 변화가 없었으나 12시간에서는 4배 이상의 높은 발현을 보였으며, Id-2 mRNA의 발현은 estrogen 처리 6시간과 12시간 모두에서 대조군에 비해 4배 가량 감소하였다. 이 실험군을 LCM을 이용하여 자궁내막상피세포, 자궁기질세포, 자궁근육층을 각각 분리하여 실험한 결과 estrogen 처리군에서 Id-1의 발현은 자궁내막상피세포에서만 높은 발현을 보였으며, estrogen 처리 6시간과 12시간에는 큰 차이를 보이지 않았다. 그러나, Id-2 mRNA는 자궁내막상피세포에서 estrogen 처리 6, 12시간 모두에서 높은 발현을 보였고, 근육세포층에서는 estrogen 처리 6시간에서는 변화가 거의 없었으나 12시간에는 현저하게 증가하였다. 단, 자궁기질세포에서는 대조군에 비해 estrogen 6, 12시간에서 Id-2 mRNA의 발현이 감소하였다. 임신한 생쥐 자궁의 착상부위에서는 Id-1 mNRA의 발현은 비착상부 위보다 월등하게 높은 증가를 보였다. 결 론: 난소절제 생쥐를 이용한 실험에서 Id-1, -3는 estrogen에 의해 발현이 증가하고, Id-2는 발현이 감소하였다. LCM을 이용한 실험에서는 Id-2는 이와는 달리 부위별 발현양상은 다르게 나타났지만 이는 넓은 부위를 차지하는 자궁기질에서의 발현감소가 전체적인 Id-2의 발현양상으로 나타난 것으로 추측된다. 착상부위에서의 Id의 발현은 Id-1만이 유일하게 월등한 증가를 보였다. 위의 결과를 종합해 볼 때 생쥐 자궁에서 Id 유전자는 estrogen에 의해 조절되며 직, 간접적으로 착상시기에 다양한 작용을 할 것으로 사료된다.

Experimental Study of Dadun(LR1) ${\cdot}$ Shaochung(HT9) ${\cdot}$ Shaofu(HT8) Reinforcement in Acupuncture on the Improvement of Cerebral Hemodynamics (대돈(大敦) ${\cdot}$ 소충(少衝) ${\cdot}$ 소부(少府) ${\cdot}$ 자침(刺鍼)이 뇌혈류역학(腦血流力學)에 미치는 영향)

  • Park, Eun-Ju;Cho, Myung-Rae
    • Journal of Acupuncture Research
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    • v.24 no.1
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    • pp.111-125
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    • 2007
  • Objection : The aim of this study was to investigate anti-ischemic effect of LR1 ${\cdot}$ HT8 ${\cdot}$ HT9 Reinforcement in Acupuncture. Methods : I designed to investigate whether LR1 ${\cdot}$ HT8 ${\cdot}$ HT9 Reinforcement in Acupuncture affects cerebral hemodynamics [regional cerebral blood flow(rCBF), pial arterial diameter(PAD), mean arterial blood pressure (MABP) ] in normal and cerebral ischemia rats by MCA occlusion method, and to make manifest whether LR1 ${\cdot}$ HT8 ${\cdot}$ HT9 Reinforcement in Acupuncture is mediated by cyclooxygenase or guanylate cyclase. The changes of rCBF and MABP were determinated by laser-doppler flowmetry(LDF), and the change of PAD was determinated by video microscope and width analyzer. Results: The results were as follows ; 1. LR1 ${\cdot}$ HT8 ${\cdot}$ HT9 Reinforcement in Acupuncture was significantly increased rCBF, PAD, but decreased MABP after withdrawing of the needle. This results suggest that LR1 ${\cdot}$ HT8 ${\cdot}$ HT9 Reinforcement in Acupuncture induced significantly rCBF by dilating PAD. 2. Pretreatment with indomethacin (1mg/kg, i.v.) was significantly inhibited LR1 ${\cdot}$ HT8 ${\cdot}$ HT9 Reinforcement in Acupuncture induced increase of rCBF and PAD, but increased LR1 ${\cdot}$ HT8 ${\cdot}$ HT9 Reinforcement in Acupuncture induced decrease of MABP after withdrawing of the needle. 3. Pretreatment with methylene blue(10/${\mu}$g/kg, i.v.) was decreased LR1 ${\cdot}$ HT8 ${\cdot}$ HT9 Reinforcement in Acupuncture induced increase of rCBF and MABP, but accelerated LR1 ${\cdot}$ HT8 ${\cdot}$ HT9 Reinforcement in Acupuncture induced decrease of PAD. This results suggest that the mechanism of LR1 ${\cdot}$ HT8 ${\cdot}$ HT9 Reinforcement in Acupuncture is mediated by cyclooxygenase or guanylate cyclase. Conclusion : I suggest that LR1 ${\cdot}$ HT8 ${\cdot}$ HT9 Reinforcement in Acupuncture has an anti-ischemic effect through the improvement of cerebral hemodynamics, and the mechanism IS mediated by cyclooxygenase.

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RF magnetron sputtering법으로 성장시킨 ZnO 박막의 광특성과 grain size의 영향에 관한 연구

  • 김경국;박성주;정형진;최원국
    • Proceedings of the Korean Vacuum Society Conference
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    • 1999.07a
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    • pp.117-117
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    • 1999
  • 최근 광소자와 더불어 발전과 더불어 고효율의 새로운 광소자에 대한 수요가 증가되고 있다. ZnO는 이러한 특성을 가진 재료중에 한가지로서 최근 들어 그 가능성에 대한 연구가 활발히 이루어지고 있다. 특히 상온에서 exciton binding energy가 다른 재료보다 큰 60meV로 고효율의 blue, UV 발광이 가능한 재료로 알려져 있다. 본 연구에서도 광소자로서 ZnO를 활용하기 위해서 RF magnetron sputtering법을 이용하기 위하여 광특성의 향상에 목적을 두고 연구하였다. ZnO 박막은 RF magnetron sputtering법을 이용하여 sapphire (0001) 기판위에 성장시켰다. RF power는 60W에서 120W까지 변화시켰고 박막의 성장온도는 55$0^{\circ}C$$600^{\circ}C$로 변화시켰으며, 박막의 성장시간은 60분, ZnO target과 기판과의 거리는 4.5cm로 하여 성장시켰다. 성장된 ZnO 박막은 XRD $\theta$-rocking scan 측정을 통해서 박막의 C-축 배향성과 RBS channeling를 이용하여 ZnO 박막의 epitaxial 성장 정도를 측정하였다. 박막의 상온 발광 특성은 He-Cd laser를 사용한 photoluminescence spectra로 측정하였다. 또한 표면의 morphology는 atomic force microscope(AFM)를 이용하여 관찰하였으며 transmission electron microscopy(TEM)을 사용하여 ZnO박막의 단면적을 관찰함으로서 grain의 성장과 광특성 및 결정성과의 영향에 대해서 연구하였다. ZnO 박막의 성장온도 55$0^{\circ}C$에서 RF power를 60W에서 120W까지 변화시킬 경우 XRD $\theta$-rocking peak의 반치폭이 0.157$^{\circ}$에서 0.436$^{\circ}$까지 변화하였고 80W에서 최소값을 가졌으며 in-plain에 대한 XRD 측정 결과 ZnO 박막의 성장은 sapphire 기판에 대해서 30$^{\circ}$회전되어 성장된 것으로 알 수 있었으며 이는 ZnO [100]∥ Al2O3[110]의 관계를 갖는다는 것을 나타낸다. 광특성의 측정 결과인 PL peak의 반치폭은 133.67meV에서 89.5meV까지 변화함을 알 수 있었고 80W에서 최대값을 가졌으며 이는 RF power의 변화에 따른 결정성의 변화와는 반대되는 현상임을 알 수 있었다. 그러나 성장온도 $600^{\circ}C$일때에는 XRD $\theta$-rocking peak의 반치폭이 0.129$^{\circ}$로 결정성이 우수한 박막임을 확인할 수 있었고 PL peak의 반치폭 또한 Ar과 O2의 비율에 따라 76.32meV에서 98.77meV로 광특성도 우수한 것으로 나타났다. RBS channeling 결과 55$0^{\circ}C$에서는 $\chi$min값이 50~60%였으나 $600^{\circ}C$일 때에는 $\chi$min값이 4~5%로 박막이 epitaxial 성장을 하였다는 것을 알 수 있었다. 결정성과 광특성과의 연관성을 알아보기 위해 TEM을 이용한 박막의 cross section image를 관찰한 결과 광특성이 우수한 시편일수록 grain의 크기가 큰 것으로 나타났고 결정성이 우수한 시편의 경우에서는 XRD분석 결과에서처럼 C-축배향성이 우수한 것을 확인할 수 있었다. 이상의 결과로부터 RF magnetron sputtering 법으로 광특성이 우수한 양질의 ZnO박막 성장이 가능하였다는 것을 알 수 있었으며 광소자로써의 가능성을 확인 할 수 있었다.

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The Analysis of Research Trend about Management of Low Back Pain (요통관리에 관한 연구동향 분석)

  • Hyun, Kyung-Sun
    • The Korean Journal of Rehabilitation Nursing
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    • v.1 no.1
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    • pp.51-60
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    • 1998
  • The result of studying papers about management of lower back pain published in domestic and foreign nursing and medical magazines in these 10 years is as follows ; 1. General characteristic of lower back pain ; 1) In sex distribution, there were more men than women in 5 papers and more women than men in 4 papers among 9 papers surveryed. 2) In age distribution, thirties to forties of patients had more lower back pain as surveyed by general hospitals and fifties to sixties of patients had more lower back pain as surveyed by oriental medical hospitals. 3) In cause factor, there were 50 to 65% of sprain, 32 to 44% of herniated intervertebral disc and 13 to 29% of degenerative changes. 4) In symtom distribution, there were 26 to 57% of lower back pain, 42 to 65% of lower back pain with radiating pain and 34 to 99% of paravertevral muscle spasm. 5) In period of pain management distribution, 18 to 40% of patients experienced pain for less than 6 months and 59 to 82% of them experienced pain for more than 6 months in 3 papers among 4 papers. 6) In surveying the treatment, 66 to 88% of patients had conservative treatment and there were treatments of general hospital, oriental medicine, self remedy and traditional practice in conservative treatment. 7) In job distribution, 12 to 50% of them were housekeepers, 23 to 31% office workers, 4.6 to 36% blue color workers and 11 to 15% students. 2. As psychological character lower back pain paients had anxiety, depression, anger-hostility, phobic anxiety, neurasthenia, hypochondriasis, and interpersonal sensitivity. 3. To distinguish the cause of lower back pain, plain lumbar roentgenogram, straight leg rasing test, eletromyelogic findings, somatosensory evoked potentials CT and MRI were performed. 4. To relieve lower back pain. epidural adhesiolysis, epidulal injection of local anesthetic in mixture with steroid, lumbar spinal root block, low level laser therapy, acupuncture like transcutaneous nerve stimulation(AL TENS), topical capsaicin and lumbar orthotics were used in medical field, and relaxation technique was used in nursing field. 5. Mckenzie's extension exercise and William's flexsion exercise for lower back pain were used in medical field and Yoga exercise was applied in nursing field. 6. The more school education and self efficacy were high, the better they had active coping lower back pain positively and the less self efficacy was the more they had serious pain. As a result of studying the paper there have been very little research for lower back pain in nursing fields of Korea and foreign countries. Because 60 to 80% of population expeience lower back pain at least more than once, it is necessary to develop the study and clinical practice for management of lower back pain.

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Photoluminescence of $Ga_2S_3$: Er Single Crystals ($Ga_2S_3$: Er 단결정의 Photoluminescence 특성 연구)

  • 진문석;김화택
    • Journal of the Korean Vacuum Society
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    • v.7 no.1
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    • pp.66-71
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    • 1998
  • Two kinds of $Ga_2S_3:Er$ (type A and type B) single crystals were grown by the chemical transport reaction method using iodine as a transport agent. The single crystals were crystallized into a monoclinic structure. The optical energy band gaps were found to 3.375 eV for the $Ga_2S_3:Er$ (type A) single crystal and 3.365 eV fir the $Ga_2S_3:Er$ (type B) single crystal at 13K. When the $Ga_2S_3:Er$ (type A and type B) single crystals were excited by the 325 nm-line of a Cd-He laser, Photoluminescence spectra of the $Ga_2S_3:Er$ (type A) single crystal exhibited blue emission band peaked at 444 nm and green and red emission bands peaked at 518 nm and 690 nm. Pgitikynubescebce soectra if the $Ga_2S_3:Er$ (typeB) single crystal showed green and red emission bands peaked at 513 nm and 695 nm. Sharp emission peaks in the two kinds if $Ga_2S_3:Er$ single crystal were observed near 525 nm, 553 nm, 664 nm, 812 nm, 986 nm, and 1540 nm and analysed as originating from the electron transitions between the energy levels of $Er^{3+}$ ion.

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An Error Analysis of the 3D Automatic Face Recognition Apparatus (3D-AFRA) Hardware (3차원 안면자동분석 사상체질진단기의 Hardware 오차분석)

  • Kwak, Chang-Kyu;Seok, Jae-Hwa;Song, Jung-Hoon;Kim, Hyun-Jin;Hwang, Min-Woo;Yoo, Jung-Hee;Kho, Byung-Hee;Kim, Jong-Won;Lee, Eui-Ju
    • Journal of Sasang Constitutional Medicine
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    • v.19 no.2
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    • pp.22-29
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    • 2007
  • 1. Objectives Sasang Contitutional Medicine, a part of the traditional Korean medical lore, treats illness through a constitutional typing system that categorizespeople into four constitutional types. A few of the important criteria for differentiating the constitutional types are external appearances, inner state of mind, and pathological patterns. We had been developing a 3D Automatic Face Recognition Apparatus (3D-AFRA) in order to evaluate the external appearances with more objectivity. This apparatus provides a 3D image and numerical data on facial configuration, and this study aims to evaluate the mechanical accuracy of the 3D-AFRA hardware. 2. Methods Several objects of different shapes (cube, cylinder, cone, pyramid) were each scanned 10 times using the 3D Automatic Face Recognition Apparatus (3D-AFRA). The results were then compared and analyzed with data retrieved through a laser scanner known for its high accuracy. The error rates were analyzed for each grid point of facial contour scanned with Rapidform2006 (Rapidform2006 is a 3D scanning software that collects grid point data for contours of various products and products and product parts through 3D scanners and other 3D measuring devices; the grid point data thusly acquired is then used to reconstruct highly precise polygon and curvature models). 3. Results and Conclusions The average error rate was 0.22mm for the cube, 0.22mm for the cylinder, 0.125mm for the cone, and 0.172mm for the pyramid. The visual data comparing error rates for measurement figures retrieved with Rapidform2006 is shown in $Fig.3{\sim}Fig.6$. Blue tendency indicates smaller error rates, while red indicates greater error rates The protruding corners of the cube display red, indicating greater error rates. The cylinder shows greater error rates on the edges. The pyramid displays greater error rates on the base surface and around the vertex. The cone also shows greater error around the protruding edge.

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Spectroscopic Comparison of Photo-oxidation of Outside and Inside of Hair by UVB Irradiation (자외선B 조사에 의한 모발 외부와 내부의 광산화에 관한 분광학적 비교)

  • Ha, Byung-Jo
    • Applied Chemistry for Engineering
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    • v.31 no.2
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    • pp.220-225
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    • 2020
  • Hair is made of proteins containing various amino acids. Ultraviolet (UV) radiation is believed to be responsible for the most damaging effects of sunlight, and also plays an important role in hair aging. The purpose of this study was to investigate the changes in morphological and chemical structures after ultraviolet B (UVB) irradiation of human hair. The UVB-irradiated hair showed characteristic morphological and structural changes, compared to those of the normal hair. The result from a scanning electron microscope (SEM) equipped with an energy dispersive X-ray diffractometer (EDX) showed that the scale of UV-irradiated hair appeared to be rough and the amount of oxygen element was higher than that of the normal hair. Fluorescence and three dimensional (3D) topographical images were obtained by a confocal laser scanning microscope (CLSM). In 3D images, the green emission intensity of normal hair was much higher than that of fluorescing UVB-irradiated hair. The intensity of green emission reflects the intrinsic fluorescence of hair protein. Also, a fluorescent imaging method using fluorescamine reagent was used to identify the free amino groups resulting from a peptide bond breakage in UVB-irradiated hair. Strong blue fluorescence of UVB-irradiated hair, which indicates a very high level of amino groups, was observed by CLSM. Therefore, the fluorescamine as an extrinsic fluorescence could provide a useful tool to identify the peptide bond breakage in UVB-irradiated hair. Infrared image mapping was also employed to assess the cross-sections of normal and UVB-irradiated specimens to examine the oxidation of disulfide bonds. The degree of peak areas with strong absorbance for the disulfide mono-oxide was spread from the outside to the inside of hair. The spectroscopic techniques used alone, or in combination, launch new possibilities in the field of hair cosmetics.

Effects of Aqua-Acupuncture of Carthami Flos(GV15) on the Changes of Cerebral Hemodynamics in Rats (아문(瘂門)(GV15)의 홍화약침(紅花藥針)이 백서(白鼠)의 뇌혈류역학(腦血流力學) 변동(變動)에 미치는 영향(影響))

  • Ahn, Young-sun;Wei, Tung-shuen;Cho, Myung-rae;Chae, Woo-seok;Yun, Yeo-choong
    • Journal of Acupuncture Research
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    • v.19 no.5
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    • pp.92-111
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    • 2002
  • Objective : Carthami Flos has been used as a herb to promote blood circulation to remove blood stasis in oriental medicine for many centuries, and Amun(GV15) has been used as a meridian point to treat apoplexy etc. To investigate treatment of cerevral vascular disease(CVA) by promoting blood circulation and removing blood stasis(活血化瘀法), we observed the experimental effects and mechanism of auqa-acupunture of Carthami Flos(ACF) injected into GV15 on cerevral hemodynamics and cardiovascular system of rats. Method : Aqua-acupuncture of Carthami Flos(ACF) was injected into GV15, and then we investigated experimental effects and mechanism of ACF on the cerebral hemodynamics[regional cerebral blood flow(rCBF), pial arterial diameter(PAD), meal arterial blood pressure(MABP)] and cardiovascular system[cardiac muscle contractile force(CMF), heart rate(HR)I by pretreatment with methylene blue(MTB) and indomethacin(IDN). The changes in rCBF, MABP, CMF and HR were tested by Laser Doppler Flowmetry(LDF), and the changes in PAD was determinated by video microscopy methods and video analyzer. Results :The results were as follows in normal rats ; The changes of rCBF and PAD were significantly increased by ACF($120{\mu}{\ell}/kg$) in a injected time-dependent manner, but MABP was not changed by ACF. The changes of cardiovascular system were increased by ACF in a injected time-dependent manner. And pretreatment with MTB was significantly inhibited ACE induced increase of rCBF and PAD, and was decreased ACF induced increase of HR. And pretreatment with IDN was increased ACF induced MABP and CMF. And the results were as follows in cerebral ischemic rats ; The changes of rCBF was increased stabilizly by treatment with ACF($120{\mu}{\ell}/kg$) in during the period of cerebral reperfusion, but pretreatment with MTB was increased ACF induced increase of rCBF during the period of cerebral reperfusion. The results were as follows in normal rats ; The changes of rCBF and PAD were significantly increased by ACF($120{\mu}{\ell}/kg$) in a injected time-dependent manner, but MABP was not changed by ACF. The changes of cardiovascular system were increased by ACF in a injected time-dependent manner. And pretreatment with MTB was significantly inhibited ACF induced increase of rCBF and PAD, and was decreased ACF induced increase of HR. And pretreatment with IDN was increased ACF induced MABP and CMF. And the results were as follows in cerebral ischemic rats ; The changes of rCBF was increased stabilizly by treatment with ACF($120{\mu}{\ell}/kg$) in during the period of cerebral reperfusion, but pretreatment with MTB was increased ACF induced increase of rCBF during the period of cerebral reperfusion Conclusions : In conclusion, ACF causes a diverse response of rCBF, PAD an HR, and action of ACF is mediated by cyclic GMP. I suggested that ACF has an anti-ischemic effect through the improvement of crebral hemodynamics in a transient cerebral ischemia.

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Efficient Red-Color Emission of InGaN/GaN Double Hetero-Structure Formed on Nano-Pyramid Structure

  • Go, Yeong-Ho;Kim, Je-Hyeong;Gong, Su-Hyeon;Kim, Ju-Seong;Kim, Taek;Jo, Yong-Hun
    • Proceedings of the Korean Vacuum Society Conference
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    • 2012.08a
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    • pp.174-175
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    • 2012
  • (In, Ga) N-based III-nitride semiconductor materials have been viewed as the most promising materials for the applications of blue and green light emitting devices such as light-emitting diodes (LEDs) and laser diodes. Although the InGaN alloy can have wide range of visible wavelength by changing the In composition, it is very hard to grow high quality epilayers of In-rich InGaN because of the thermal instability as well as the large lattice and thermal mismatches. In order to avoid phase separation of InGaN, various kinds of structures of InGaN have been studied. If high-quality In-rich InGaN/GaN multiple quantum well (MQW) structures are available, it is expected to achieve highly efficient phosphor-free white LEDs. In this study, we proposed a novel InGaN double hetero-structure grown on GaN nano-pyramids to generate broad-band red-color emission with high quantum efficiency. In this work, we systematically studied the optical properties of the InGaN pyramid structures. The nano-sized hexagonal pyramid structures were grown on the n-type GaN template by metalorganic chemical vapor deposition. SiNx mask was formed on the n-type GaN template with uniformly patterned circle pattern by laser holography. GaN pyramid structures were selectively grown on the opening area of mask by lateral over-growth followed by growth of InGaN/GaN double hetero-structure. The bird's eye-view scanning electron microscope (SEM) image shows that uniform hexagonal pyramid structures are well arranged. We showed that the pyramid structures have high crystal quality and the thickness of InGaN is varied along the height of pyramids via transmission electron microscope. Because the InGaN/GaN double hetero-structure was grown on the nano-pyramid GaN and on the planar GaN, simultaneously, we investigated the comparative study of the optical properties. Photoluminescence (PL) spectra of nano-pyramid sample and planar sample measured at 10 K. Although the growth condition were exactly the same for two samples, the nano-pyramid sample have much lower energy emission centered at 615 nm, compared to 438 nm for planar sample. Moreover, nano-pyramid sample shows broad-band spectrum, which is originate from structural properties of nano-pyramid structure. To study thermal activation energy and potential fluctuation, we measured PL with changing temperature from 10 K to 300 K. We also measured PL with changing the excitation power from 48 ${\mu}W$ to 48 mW. We can discriminate the origin of the broad-band spectra from the defect-related yellow luminescence of GaN by carrying out PL excitation experiments. The nano-pyramid structure provided highly efficient broad-band red-color emission for the future applications of phosphor-free white LEDs.

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Modulation of Adhesion Proteins Integrin β1 and FAK, and Cytoskeletal Protein Actin by Spermine in MCF-7 Cells (MCF-7 세포에서 spermine에 의한 부착단백질 Integrin β1과 FAK, 세포골격 단백질 actin의 조절)

  • Jee, Hye-Jin;Kim, Byeong-Gee
    • Journal of Life Science
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    • v.22 no.1
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    • pp.16-24
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    • 2012
  • Polyamines are essential for cell growth and differentiation; however their precise roles are unclear yet. In the present study, the cytotoxic effect of spermine (spm) on MCF-7 cells was investigated. In the MTT assay of MCF-7 cells treated with spm, cell viability was significantly decreased in a time-and dose-dependent manner. Cell viability measurement was confirmed by trypan blue staining. FACS analysis shows that sub-G1 was increased in a time-and dose-dependent manner too. When the cells were treated with spm, cells started to show morphological changes within 2 hrs. The expression of adhesion proteins (FAK and integrin ${\beta}1$), and cytoskeletal protein (actin) was checked by Western blotting analysis. Integrin ${\beta}1$ levels were slightly decreased, and FAK and actin levels were rapidly decreased with spm treatment. In confocal laser scanning microscopy, the distribution of actin did not change but the expression decreased in a dose-dependent manner with spm treatment. FAK was evenly distributed under the plasma membrane in the untreated control. However, at 10 ${\mu}M$ spm FAK seemed to move toward the cell nucleus. Integrin ${\beta}1$, which was mainly found in the focal point of the plasma membrane in the untreated control, dispersed through the entire plasma membrane in spm treatment. The present results indicate that cytotoxic effects of spm are triggered by the disruption of adhesion proteins and cytoskeletal protein.