Anisotropic Magnetization and Charge Density Wave in a Na0.78CoO2 Single Crystal

이종수,J. B. Peng,S. M. Lee,C. T. Lin 한국물리학회 2008 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.52 No.2

Single crystals of γ-Na0.78CoO2 were grown using the floating zone method. The static magnetic susceptibility M/H(T) of Na0.78CoO2 showed significant anisotropic behavior for different crystal orientations of H ∥ (ab) and H ∥ (c). While (M/H)ab(T) for a magnetic field H= 1 T in an ab-plane followed the Curie-Weiss law at high temperatures (T ≥ 100 K), (M/H)c(T) for H ∥ c-axis deviated from Curie-Weiss behavior, which may be understood by using phonon localization from strong electron-phonon coupling. The impurity spin-1/2 effect, dressed by spin fluctuation, was significant at low temperatures (T ≤ 30 K) for both field orientations of H ∥ (ab) and H ∥ (c). The electrical resistivity ρ(T) of Na0.78CoO2 showed a clear metallic character down to 16 K, with a weak increase in the resistivity ρ(T) at low temperatures T ≤ 16 K). The gap-like behavior of ρ(T) was insensitive to applied magnetic fields up to 7 T, which indicates a non-degenerate charge gap. The electrical conductivity σ(T) followed the density wave behavior with a small energy gap (0.64 meV) at low temperatures. We discussed the electrical resistivity ρ(T)$ and the anisotropic M/H(T) behavior of Na0.78CoO2 in terms of the charge density wave and a strong electron-phonon interaction. Single crystals of γ-Na0.78CoO2 were grown using the floating zone method. The static magnetic susceptibility M/H(T) of Na0.78CoO2 showed significant anisotropic behavior for different crystal orientations of H ∥ (ab) and H ∥ (c). While (M/H)ab(T) for a magnetic field H= 1 T in an ab-plane followed the Curie-Weiss law at high temperatures (T ≥ 100 K), (M/H)c(T) for H ∥ c-axis deviated from Curie-Weiss behavior, which may be understood by using phonon localization from strong electron-phonon coupling. The impurity spin-1/2 effect, dressed by spin fluctuation, was significant at low temperatures (T ≤ 30 K) for both field orientations of H ∥ (ab) and H ∥ (c). The electrical resistivity ρ(T) of Na0.78CoO2 showed a clear metallic character down to 16 K, with a weak increase in the resistivity ρ(T) at low temperatures T ≤ 16 K). The gap-like behavior of ρ(T) was insensitive to applied magnetic fields up to 7 T, which indicates a non-degenerate charge gap. The electrical conductivity σ(T) followed the density wave behavior with a small energy gap (0.64 meV) at low temperatures. We discussed the electrical resistivity ρ(T)$ and the anisotropic M/H(T) behavior of Na0.78CoO2 in terms of the charge density wave and a strong electron-phonon interaction.

임신 및 각종 갑상선질환에서 갑상선 기능 판정에 관한 연구 : 혈청유리 T4의 진단적 의의에 관한 고찰 The diagnostic value of free thyroxine by RIA

이종철,유명희,윤휘중,신영태,정순일,조보연,이문호,이명철 대한핵의학회 1981 핵의학 분자영상 Vol.15 No.1

To evaluate the diagnostic accuracy of the measurement of free thyroxine(FT4) by radioimmunoassay, we measured free T4 and T4, T3, T3RU, TSH and TBG serum levels by radioimmunoassay in 18 healthy persons and 52 patients with various thyroid diseases and 11 normal pregnant women. The results are as follows. 1) In 19 cases of overt hyperthyroidism, T3, free T4 and FTI, T4/TBG ratio reflect hyperfunction in all cases. T4 is increased in 94%(18/19) and TBG and TSH are decreased in 79%(15/19). 2) In 8 patients with overt hypothyroidism, TSH is increased in all cases and free T4 and FTI is decreased in all cases. T4 is decreased in 87.5%(7/8), T3 is decreased in 75%(6/8) and T4/TBG ratio is decreased in 62.5%(5/8). 3) In 5 patients who are clinically in euthyroid state after treatment of hyperthyroidism, T4 free T4, FTI and TSH are in the normal range in all cases and T3 is normal in 60%(3/5) and slightly increased in 40%(2/5). 4) In 10 patients who showed clinically borderline hypothyroidism after treatment of hyperthyroidism, TSH is increased in all cases and free T4 and FTI are decreased in all cases, but T4 and T3, T4/TBG ratio are in the normal limit in all cases. So after treatment of hyperthyroidism, TSH, free T4 or FTI are recommended as optimal function test. 5) In normal pregnancy, free T4, FTI and T4/TBG ratio reflect normal function, but the other parameters unreliable due to the influence of increased TBG. Also TBG and TSH level in pregnancy is increased significantly compared with normal healthy control group. 6) The coefficients of correlation between T4 and FTI were 0.862(p〈0.001) and 0.685(p〈0.001) between free T4 and T4/TBG ratio. In most patients, diagnostic value of free T4 was comparable and even superior to FTI, so free T4 measurement can be used routinely with thyrotropin assay in the diagnosis of hypothyrodism or with T3 for the diagnosis of hyperthyroidism.

소 c-KIT Receptor 유전자의 다형성에 관한 연구

장요순,김태헌,윤두학,박응우,이혜원,이학교,정일정 한국동물자원과학회 2002 한국축산학회지 Vol.44 No.6

소의 흰 반점 관련 후보유전자로 c-KIT receptor 유전자를 선정하여, c-KIT receptor 유전자내의 변이를 탐색하고 변이가 흰반점 표현형과 연관성이 있는지를 분석하였다. 한우, Angus, Brown Swiss, Charolais, Hereford, Holstein, Limousin 및 Simmental 등 8개 품종의 DNA 시료를 사용하여 c-KIT receptor 유전자의 intron 6번 영역에서 다형성을 조사하고 분석하였다. c-KIT receptor 유전자의 intron 6번 영역에서는 4개의 염기치환이 발견되어, MspⅠ, BsrBⅠ 및 NdeⅠ 제한효소를 이용하여 PCR-RFLP 분석을 실시하였다. Intron 6번을 포함하는 영역의 PCR 산물 크기는 2,440 bp 이었다. MspⅠ다형성은 PCR-RFLP 분석 결과 3개의 대립유전자가 존재하였으며, 한우품종에서는 3개의 대립유전자 모두가 발견되었고, CC 형태이 유전자형을 제외한 5개의 유전자형 (AA, AB, AC, BC 및 BB)을 확인하였다. Angus, Brown Swiss, Hereford, Holstein 및 Simmental 품종에서는 A 대립유전자만을 갖는 것으로 조사되었고, 한우는 44%만 AA 유전자형을 나타내었다. BsrBⅠ 다형성은 2개의 대립유전자로서 3개의 유전자형이 나타나는 것을 확인하였으며, Charolais 및 Hereford 품종이 다른 소 품종에 비하여 A 대립유전자의 빈도가 높게 나타났다. NdeⅠ 다형성을 분석한 결과 Brown Swiss 품종에서는 NdeⅠ에 의해 절단되는 형태인 A 대립유전자만 관찰되었으며, Holstein 품종은 92%, Simmental 품종은 72%가 절단되는 형태를 나타내어, 모색이 흰색을 띠는 소 품종에서 절단되는 형태가 많았다. 소 c-KIT receptor 유전자의 intron 6번 영역에서 확인된 4개의 염기치환은 품종에 따라 다른 빈도를 보였으나, 이들 염기치환과 흰 반점과의 연관성에 대한 증거는 발견하지 못하였다. 그러므로 소의 흰 반점과 c-KIT receptor 유전자 내의 변이와의 관련성은 다른 영역에 대한 추가적인 분석과, 이미 보고된 다른 모색관련 유전자의 다형성과의 연관성 분석 등과 같은 연구가 필요한 것으로 판단된다. We considered KIT gene as a candidate gene for the white-spotting pattern in cattle. This study was carried out to detect genetic variation of c-KIT receptor gene and to investigate association between the mutation and the white-spotting pattern in cattle. PCR-RFLP analysis within intron 6 of c-KIT receptor gene were performed with 8 cattle breeds including Hanwoo, Angus, Brown Swiss, Charolais, Hereford, Holstein, Limousin and Simmental. When PCR product of approximately 2,440 bp including intron 6 of c-KIT receptor gene was sequenced, four nucleotide substitutions were found within intron 6 of the bovine c-KIT receptor gene. In PCR-RFLP analysis, three alleles (A, B and C), two alleles (A and B) and two alleles (A and B) at each locus were identified by Msp Ⅰ, BsrBⅠ and NdeⅠ, respectively. Although frequencies of allele at each locus were different among cattle breeds, we could not get any evidence related with white or white spotting phenotypes in these mutations on intron 6 of c-KIT receptor gene. However, we can not entirely exclude the possibility that c-KIT receptor gene is responsible for white spotting phenotype in cattle. Thus, further studies need to detect other mutations in c-KIT receptor gene and to test association of those mutations and coat color phenotypes in cattle.

<i>Rhodococcus aerolatus</i> sp. nov., isolated from subarctic rainwater

Hwang, C. Y.,Lee, I.,Cho, Y.,Lee, Y. M.,Baek, K.,Jung, Y.-J.,Yang, Y. Y.,Lee, T.,Rhee, T. S.,Lee, H. K. International Union of Microbiological Societies 2015 International journal of systematic and evolutiona Vol.65 No.2

<P>A Gram-stain-positive, rod-shaped and non-motile strain, designated PAMC 27367<SUP>T</SUP>, was isolated from rainwater collected on the Bering Sea. Analysis of the 16S rRNA gene sequence of the strain showed an affiliation with the genus <I>Rhodococcus</I>. Phylogenetic analyses revealed that strain PAMC 27367<SUP>T</SUP> formed a robust clade with the type strains of <I>Rhodococcus rhodnii</I>, <I>Rhodococcus aetherivorans</I> and <I>Rhodococcus ruber</I> with 16S rRNA gene sequence similarities of 96.3 %, 95.8 % and 95.5 %, respectively. Cells of the strain grew optimally at 25 °C and at pH 6.5–7.0 in the presence of 0–2 % (w/v) sea salts. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannoside and three unknown phospholipids. The major cellular fatty acids (>10 %) were iso-C<SUB>16 : 0</SUB>, C<SUB>17 : 1</SUB>ω8<I>c</I> and 10-methyl C<SUB>17 : 0</SUB>. Cell wall analysis showed that strain PAMC 27367<SUP>T</SUP> contained <I>meso</I>-diaminopimelic acid. The genomic DNA G+C content was 77.1 mol%. Based on the phylogenetic, chemotaxonomic and phenotypic data presented here, we propose a novel species with the name <I>Rhodococcus</I> <I>aerolatus</I> sp. nov., with PAMC 27367<SUP>T</SUP> ( = KCTC 29240<SUP>T</SUP> = JCM 19485<SUP>T</SUP>) as the type strain.</P>

Chemical inhibitors of c-Met receptor tyrosine kinase stimulate osteoblast differentiation and bone regeneration

Kim, J.W.,Lee, M.N.,Jeong, B.C.,Oh, S.H.,Kook, M.S.,Koh, J.T. North-Holland 2017 European journal of pharmacology Vol.806 No.-

<P>The c-Met receptor tyrosine kinase and its ligand, hepatocyte growth factor (HGF), have been recently introduced to negatively regulate bone morphogenetic protein (BMP)-induced osteogenesis. However, the effect of chemical inhibitors of c-Met receptor on osteoblast differentiation process has not been examined, especially the applicability of c-Met chemical inhibitors on in vivo bone regeneration. In this study, we demonstrated that chemical inhibitors of c-Met receptor tyrosine kinase, SYN1143 and SGX523, could potentiate the differentiation of precursor cells to osteoblasts and stimulate regeneration in calvarial bone defects of mice. Treatment with SYN1143 or SGX523 inhibited HGF-induced c-Met phosphorylation in MC3T3-E1 and C3H10T1/2 cells. Cell proliferation of MC3T3-E1 or C3H10T1/2 was not significantly affected by the concentrations of these inhibitors. Co-treatment with chemical inhibitor of c-Met and osteogenic inducing media enhanced osteoblast-specific genes expression and calcium nodule formation accompanied by increased Runx2 expression via c-Met receptor-dependent but Erk-Smad signaling independent pathway. Notably, the administration of these c-Met inhibitors significantly repaired critical-sized calvarial bone defects. Collectively, our results suggest that chemical inhibitors of c-Met receptor tyrosine kinase might be used as novel therapeutics to induce bone regeneration.</P>

한우 수소 증체시 (增體時) 에너지 및 단백질 축적효율에 관한 연구

이상철(S . C . Lee),강태홍(T . H . Kang),한인규(In K . Han) 한국영양사료학회 1991 韓國營養飼料學會誌 Vol.15 No.3

한우에 대한 농후사료 (濃厚飼料) 급여가 전체사료의 에너지사용효율 및 비육에 미치는 영향

이상철(S . C . Lee),이봉재(B . J . Lee),강태홍(T . H . Kang),김강식(K . S . Kim) 한국영양사료학회 1988 韓國營養飼料學會誌 Vol.12 No.4

Sorghum × Sudangrass hybrid 의 입모저장에 관한 연구 ; 1 . 입모저장기간이 생육특성 및 기호성 변화에 미치는 영향

이상무 ( S M Lee ),문상호 ( S H Moon ),백인철 ( I C Baek ),전병태 ( B T Jeon ) 한국축산학회 1994 한국축산학회지 Vol.36 No.1

Growth characteristics and palatability by different harvesting dates were measured in order to determine its availability and effective storage period when sorghum × sudangrass hybrid were stored as foggage. Experiment was carried out with six treatments as follows; T1, T2 and T3 were foggaged at 120, 160 and 200㎝ in plant length and T4, T5 and T6 were foggaged at boot, milk and dough stage on 7 october after regrowth respectively. Rice straw was offered to examine the relative palatability a, control. 1. Growth characteristics such as plant length, leaf length, leaf width, leaf number and stem hardness were decreased with prolongation of foggage period at all treatments. Especially, decrease and falling ratio were a heigher at T5 and T6 than the other treatments. 2. Greeness grade of leaf showed fast decoloration at TI and T2 treatments, but stem showed fast decoloration at TS and T6 treatments. Leaf and stem decolorized in mid-October and mid-november in all treatments. 3. Leaf ratio was deceased with prolongation of foggage period, but stem showed gradually increase. Grain ratio was stable increase at T6 treatments, but not at T5 treatment, 4. Dry matter contents of leaf and grain were stable increased at all treatment but stem was multifarious according to weather conditions. 5. Changes of palatability were high at T1, T2 and T3 treatments untill mid-October, but T4 treatment and rice straw showed high in early December. 6. According to the results obtained in this study, it was suggested that when sorghum x sudangrass hybrid is used as foggage, foggaging period would be suitable until mid-november and growth stage for foggaging would be recommendable from T2 to boot stage for maximum availability.

Ex-situ catalytic pyrolysis of citrus fruit peels over mesoporous MFI and Al-MCM-41

Kim, Y.M.,Jae, J.,Lee, H.W.,Han, T.U.,Lee, H.,Park, S.H.,Kim, S.,Watanabe, C.,Park, Y.K. Pergamon ; Elsevier Science Ltd 2016 Energy conversion and management Vol.125 No.-

The thermal and ex-situ catalytic pyrolysis of different citrus peels, Citrus paradisi peel, Citrus sinensis peel, Citrus unshiu peel, and Citrus limon peel, were studied by thermogravimetric, evolved gas analysis-mass spectrometry and tandem micro-reactor-gas chromatograph/mass spectrometry analyses. Kinetic analysis revealed more complicated reaction steps and a wider range of activation energies of citrus peels than those of wood powder due to the presence of pectin in the citrus peels. Large amounts of methanol formation from each citrus peel were also recorded by evolved gas analysis-mass spectrometry and fast pyrolysis-gas chromatograph/mass spectrometry analyses at the main decomposition temperature of pectin, between 150 and 250<SUP>o</SUP>C. Mesoporous MFI was found to be a more effective catalyst for the production of mono aromatic compounds (benzene, toluene, ethylbenzene, and xylene; 3.06-4.17C%) and light olefins (ethene, propene, butene, and butadiene; 8.13-9.13C%) than Al-MCM-41 (mono aromatic compounds 0.67-0.93C% and light olefins 3.61-4.58C%) because of its higher catalytic activity in deoxygenation and aromatization due to the stronger acidity of mesoporous MFI. The yield of mono aromatic compounds over mesoporous MFI was highest from C. paradisi peel (4.17C%), followed in order by C. sinensis peel (3.83C%), C. unshiu peel (3.61C%), and C. limon peel (3.06C%), due mainly to the different contents and properties of pectin in each citrus peel. The higher activities of mesoporous MFI than Al-MCM-41 were also maintained during the 7 times sequential catalytic pyrolysis of C. paradisi peel, demonstrating the stability of mesoporous MFI catalyst.

정상 임신에서 임신주기에 따른 갑상선기능의 변화

김원배,정재훈,윤보현,이석인,김민선,오태근,조보연,이홍규,고창순 대한내분비학회 1994 Endocrinology and metabolism Vol.9 No.3

It is well known that normal pregnancy is accompanied by a rise in serum concentrations of thyroxine-binding globulin(TBG) and human chorionic gonadotropin (hCG). Alterations of biochemical parameters of thyroid function are recognized during gestation and sensitive tests to evaluate the alterations easily are required. Therefore, a cross-sectional study was undertaken in 140 healthy pregnant women to evaluate the efficacy of free T_4 measured by 2-step RIA compared to other thyroid function tests and to confirm the changes of thyroid function according to the stages of normal pregnancy. The sensitivities of free T_4 index, free T_4(by 2-step RIA), T_3 and TSH were realtively high(99.3%, 93.6%, 92.9%, 83.6%, respectively) compared to those of T_4 and T_3 bead upgake(49.3%, 21.4%) during all stages of pregnancy. There were positive correlations between free T_4 index and free T_4 or total T_4(r=0.68, r=0.72; p$lt;0.001). The values of free T_4 index sharply decreased from 3.22+-0.10(meam +-SEM) during 6th-12th week to an plateau after 16th-20th week of gestation(p$lt;0.01). The serum concentrations free T_4 and T_3 bead uptake also significantly decreased from 1.65+-0.05 ng/dl, 24.7+- 0.7% during 6th-12th week to an plateau after 16th-20th week of gestation, respectively(p$lt;0.001), No differences were found in the changes of serum concentrations of T_3, T_4 and TSH according to the stages of pregnancy. In conclusion, it is adequate to measure some tests including free T_4 index and free T_4 to evaluate thyroid function during pregnancy. The thyroid physiology and changes of thyroid function according to the stages of pregnancy should be considered in the interpretation of thyroid function status during pregnancy(J Kor Soc Endocrinol 9: 183-189, 1994).