• Title/Summary/Keyword: $ND_L$

Search Result 976, Processing Time 0.036 seconds

Exciton reflection and $A_{EP}$ line of 2H-$PbI_2$ single crystal (2H-$PbI_2$ 단결정의 엑시톤 반사 및 $A_{EP}$선에 관한 연구)

  • 김현철;송인걸;유종인;유연석;나훈균
    • Korean Journal of Optics and Photonics
    • /
    • v.7 no.3
    • /
    • pp.227-231
    • /
    • 1996
  • The reflection spectrum of a $2H-PbI_2$ single crystal grown by vapour phase method were measured at 10 K near the fundamental absorption edge. The n= 1,2,3 Wannier exciton series and $A_{EP}$ reflection line were obtained from the reflection spectrum. Based on the 2nd phonon energy in the Raman spectrum, which is different from Nagamune's report, we suggest that $A_{EP}$ line is due to the bound state between the n=2 exciton and the 2nd phonon which surmise that this is LO phnon due to the second Raman process. The L-T splitting energy of n=1 exciton line was 6.56 meV and was consistent with the emission spectrum. The temperature dependence of the reflection spectrum showed that n=1 exciton peak was shifted to longer wavelength while, as the temperatre is raised, the sharpness of that with the increase of the L-T splitting energy decrease. From Wannier exiton series, the exciton binding energy and exciton radius was 30 meV and 14$\AA$, respectively.

  • PDF

Prevalence of Disc Degeneration in Asymptomatic Korean Subjects. Part 1 : Lumbar Spine

  • Kim, Sang Jin;Lee, Tae Hoon;Lim, Soo Mee
    • Journal of Korean Neurosurgical Society
    • /
    • v.53 no.1
    • /
    • pp.31-38
    • /
    • 2013
  • Objective : Asymptomatic patients show high degeneration prevalence at lumbar disc in previous literatures. Unfortunately, there are few Korean data, so the authors attempted to analyze the prevalence of disc degeneration in highly selective asymptomatic Korean subjects using MRI. Methods : We performed 3 T MRI sagittal scans from T12 to S1 on 102 asymptomatic subjects (50 men and 52 women) who visited our hospital between the ages of 14 and 82 years (mean age 46.3 years). All images were read independently by three observers (two neurosurgeons and one neuroradiologist) who were not given any information about the subjects. We classified grading for lumbar disc herniation (HN), annular fissure (AF), and nucleus degeneration (ND), using disc degeneration classification. Results : The prevalence of HN, AF, and ND were 81.4%, 76.1%, and 75.8% respectively. Almost all levels showed an age-related proportional tendency with some exceptions. Conclusion : In asymptomatic Korean subjects, the abnormal findings showed high prevalence of AF, ND, and extrusion. Especially in young ages, the authors found that bulging, protrusion, and AF showed high prevalence at L4/5 and L5/S1. And ND showed high prevalence at L5/S1. So, all lumbar disc degenerations are not pathologic, especially in children and adolescents.

Complete Mitochondrial Genome Sequence and Genetic Diversity of Duroc Breed (돼지 Duroc 품종에서 미토콘드리아 유전체 서열의 특성과 집단의 유전적 다양성)

  • Cho, 1.C.;Han, S.H.;Choi, Y.L.;Ko, M.S.;Lee, J.G;Lee, J.H;Jeon, J .T
    • Journal of Animal Science and Technology
    • /
    • v.46 no.6
    • /
    • pp.937-946
    • /
    • 2004
  • Duroc is widely used to improve the meat quality and productivity. To elucidate the phylogenetic relation and the sequence specificity for the maternal property, the complete sequence of mitochondrial genome was determined and the population diversity of Duroc was investigated in this study. The length of mtDNA tested is 16,584-bp. There are several insertion/deletion mutations in the control region and coding regions for tRNA and rRNA, respectively, but not in peptide-coding regions. Four peptide-coding genes(COⅡ, COⅢ, ND3 and ND4) showed incomplete termination codon sequences such as T--, and two(ND2 and ND4L) did alternative initiation codons(AIC), respectively. Especially, the initiation codon sequences of ND2 gene were polymorphic in this population. Polymorphisms were detected in 11-bp duplication motif within control region as well as ND2 and CYTB. Variation patterns observed from the tests on three mtDNA regions were linked completely and then two haplotypes obtained from combining the data dividing this population. Duroc mtDNA is observed at the European pig cluster in the phylogenetic tree, however, the results from the population analyses supported previous opinions. This study suggests that the breed Duroc was mainly originated from the European pig lineage, and Asian lineage was also used to form the pig breed Duroc as maternal progenitors.

Clinical trial of leptospires vaccine on it immunogenicity and safety (렙토스피라 백신의 면역성 및 안전성에 관한 임상적 연구)

  • Yoon, Hyeong-Ryeol;Kim, Jeong-Soon;Heo, Yong
    • Journal of Preventive Medicine and Public Health
    • /
    • v.23 no.1 s.29
    • /
    • pp.57-64
    • /
    • 1990
  • Since the reservoir of leptospires organism is consisted of a broad spectrum of animals, the best method of prevention is vaccination. The clinical trial of leptospires vaccine conducted on human volunteer for its immunogenicity and safety. Summarized results are as following : 1. The Oral temperature among vaccinated group ranged from $36.7{\pm}0.46^{\circ}C\;to\;37.0{\pm}0.34^{\circ}C$, while in placebo injected group it ranged from $36.4{\pm}0.46^{\circ}C\;to\;36.7{\pm}0.53^{\circ}C$. There was no association between vaccination and fever (p>0.05) 2. Mild local reactions revealed in vaccinees were swelling (50-75% ), Redness($75{\sim}90%$), and induration ($25{\sim}40%$). Placebo injected group revealed only redness in 12.5% in 1st injection and 37.5% in second injection. The duration local reactions on injection site for th vaccinees and place groups disappeared within 48 hours. 3. Generalized Symptoms complained by the vaccinees were myalgia (25%), back pain(15%), headache (15%), pruritus(15%), and abdominal pain(10%), whereas placebo group complained of headache (25%), myalgia(12.5%), back pain(12.5%), pain in eyes(12.5%), abdominal pain(12.5%) pruritus (12.5%) and nausea(12.5%). 4. The serological test(MAT) of vaccinees showed geometric mean antibody titer as follows : a. L. icterohemorrhagiae lai 1 week after 1st vaccination : 22.45 1 week after 2nd vaccination : 111.23 3 week after 2nd vaccination : 266.64 b. L. canicola canicola 1 week after 1st vaccination : 24.62 1 week after 2nd vaccination : 123.92 3 week after 2nd vaccination : 276.55 c. L. icterohemorrhagiae copenhageni 1 week after 1st vaccination : 28.28 1 week after 2nd vaccination : 128.55 3 week after 2nd vaccination : 247.88 Whereas all of the place injected group showed below 1:20 titers. The sero-conversion rate of vaccinees were 100 percent.

  • PDF

Heavy Metal Distributions of Soils in the Vicinity of Shi-Hwa Industrial Complex Region (시화공업단지 주변지역 토양의 중금속 분포)

  • 송영배;이상모
    • Journal of Soil and Groundwater Environment
    • /
    • v.8 no.2
    • /
    • pp.87-91
    • /
    • 2003
  • This study was carried out to investigate the heavy metal distributions of soils in the vicinity of Shi-Hwa industrial complex region, where the air pollutants from industrial area could affect the soil environment of near residential and green areas. The ranges of contents of As, Cd, Co, Cr, Cu, Hg, Ni, Pb and Zn in soils were 0.58~3.81, ND~0.91, 0.15~6.33, ND~l.86, 0.14~110.27, ND~l.17, 0.04~10.59, 1.16~86.48 and 1.83~212.65 mg/kg, respectively. For all industrial, residential and green areas, the heavy metal contents were much lower than the standard of Korean Soil Environmental Preservation Act or the critical concentration which phytotoxicity is considered to be possible. Mean values of contents of As were similar in industrial, residential and green areas. However, the mean values of contents of Cd and Cr in industrial area were higher 10 and 5 times than those in residential and green area, respectively. And also the mean values of contents of Co, Cu, Hg, Ni, Pb and Zn in industrial area were higher 2~3 times than those in residential and green area.

Effects of Bronchoscopic Nd-YAG Laser Therapy in Tuberclous Tracheobronchial Fibrostenosis (기관 및 기관지결핵에 의한 반흔성 기도협착에 대한 기관지경적 Nd-YAG 레이저 치료의 효과)

  • Park, Jae-Yong;Jung, Tae-Hoon
    • Tuberculosis and Respiratory Diseases
    • /
    • v.41 no.5
    • /
    • pp.494-503
    • /
    • 1994
  • Background: Fibrostenosis of large airway due to tuberculosis is one of the most perplexing clinical problems not only because it can lead to respiratory failure but also because of difficulty in the management. No one technique, such as balloon dilatation or insertion of self expandable metallic stent, has proved totally satisfactory in the management of fibrostenosis. We evaluated the effect of laser therapy in patient with severe fibrostenosis due to tuberculosis. Method: We classified the fibrostenosis to three types by bronchoscopic finding - the diaphragm type: stenosed by fibrous diaphragm, sparing the tracheobronchial wall, the collapse type: stenosed by collapse of the wall due to destruction of the cartilage, and the combined type: stenosed by nonspecific inflammatory scar tissue within internal lumen with collapse of the wall. We have treated 10 patients complaining dyspnea due to with severe fibrostenosis of the diaphargm or the combined type using a neodymiumyttrium aluminum garnet(Nd-Y AG) laser through a flexible bronchoscopy. Results: Eight of the 10 cases improved after laser therapy and maintained during a follow up period of average 31.9 months. All of the cases undergoing laser therapy showed no serious complication to need the therapy. Conclusion: The results of our present study indicate that the Nd-YAG laser therapy is an effective and safe method for the management of selective tuberculous fibrostenosis.

  • PDF

I-V Characteristics of Praseodymium-Based ZnO Varistors Doped with Neodymium (네오디뮴이 첨가된 프라세오디뮴계 ZnO 바리스터의 I-V 특성)

  • 박춘현;윤한수;남춘우
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 1999.05a
    • /
    • pp.312-316
    • /
    • 1999
  • I-V characteristics of Praseodymium-based ZnO varistor doped with $Nd_2O_3$ in the range 0.0-2.0mol% sintered at 130$0^{\circ}C$ and 135$0^{\circ}C$ were investigated. In the all sides, ZnO varistors sintered at $1300^{\circ}C$ exhibited much better varistor characteristics than that at 135$0^{\circ}C$. All ZnO varistors doped with $Nd_2O_3$ sintered at $1300^{\circ}C$ exhibited good varistor characteristics but particularly ZnO varistor doped with l.Omol% $Nd_2O_3$ exhibited the best characteristics, which the nonlinear is 65.2 and the leakage current is 4.5pA. It is estimated that ZnO varistor doped with l.Omol% $Nd_2O_3$ will begin to be sufficiently used as basic composition to fabricate a good varistor.

  • PDF