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.

Measurement of the ratio of the production cross sections times branching fractions of B c ± → J/ψπ ± and B± → J/ψK ± and ℬ B c ± → J / ψ π ± π ± π ∓ / ℬ B c ± → J / ψ π ± $$ \mathrm{\mathcal{B}}\left({\mathrm{B

Khachatryan, V.,Sirunyan, A. M.,Tumasyan, A.,Adam, W.,Bergauer, T.,Dragicevic, M.,Erö,, J.,Fabjan, C.,Friedl, M.,Frü,hwirth, R.,Ghete, V. M.,Hartl, C.,Hö,rmann, N.,Hrubec, J.,Jeitler, M.,K Institute of Physics Pub 2015 The journal of high energy physics Vol.2015 No.1

<P>The ratio of the production cross sections times branching fractions (sigma(B-c(+/-))B(B-c(+/-) -> J/psi pi(+/-)))/(sigma(B-+/-)B(B-+/- -> J/psi K-+/-)) is studied in proton-proton collisions at a center-of-mass energy of 7TeV with the CMS detector at the LHC. The kinematic region investigated requires B-c(+/-) and B-+/- mesons with transverse momentum p(T) > 15 GeV and rapidity vertical bar y vertical bar < 1.6. The data sample corresponds to an integrated luminosity of 5.1 fb(-1). The ratio is determined to be [0.48 +/- 0.05 (stat) +/- 0.03 (syst) +/- 0.05 (tau(Bc))]%. The B-c(+/-) -> J/psi pi(+/-)pi(+/-)pi(-/+) decay is also observed in the same data sample. Using a model-independent method developed to measure the efficiency given the presence of resonant behaviour in the three-pion system, the ratio of the branching fractions B-c(+/-) -> J/psi pi(+/-)pi(+/-)pi(-/+)/B(B-c(+/-) -> J/psi pi(+/-)) is measured to be 2.55 +/- 0.80 (stat) +/- 0.33 (syst)(-0.01)(+0.04) (tau(Bc)), consistent with the previous LHCb result.</P>

J-PLUS: Identification of low-metallicity stars with artificial neural networks using SPHINX

Whitten, D. D.,Placco, V. M.,Beers, T. C.,Chies-Santos, A. L.,Bonatto, C.,Varela, J.,Cristó,bal-Hornillos, D.,Ederoclite, A.,Masseron, T.,Lee, Y. S.,Akras, S.,Borges Fernandes, M.,Caballero, J. Springer-Verlag 2019 Astronomy and astrophysics Vol.622 No.-

<P><I>Context.</I> We present a new methodology for the estimation of stellar atmospheric parameters from narrow- and intermediate-band photometry of the Javalambre Photometric Local Universe Survey (J-PLUS), and propose a method for target pre-selection of low-metallicity stars for follow-up spectroscopic studies. Photometric metallicity estimates for stars in the globular cluster M15 are determined using this method.</P><P><I>Aims.</I> By development of a neural-network-based photometry pipeline, we aim to produce estimates of effective temperature, <I>T</I>eff, and metallicity, [Fe/H], for a large subset of stars in the J-PLUS footprint.</P><P><I>Methods.</I> The Stellar Photometric Index Network Explorer, SPHINX, was developed to produce estimates of <I>T</I>eff and [Fe/H], after training on a combination of J-PLUS photometric inputs and synthetic magnitudes computed for medium-resolution (<I>R</I> ~ 2000) spectra of the Sloan Digital Sky Survey. This methodology was applied to J-PLUS photometry of the globular cluster M15.</P><P><I>Results.</I> Effective temperature estimates made with J-PLUS Early Data Release photometry exhibit low scatter, σ(<I>T</I>eff) = 91 K, over the temperature range 4500 < <I>T</I>eff (K) < 8500. For stars from the J-PLUS First Data Release with 4500 < <I>T</I>eff (K) < 6200, 85 ± 3% of stars known to have [Fe/H] < −2.0 are recovered by SPHINX. A mean metallicity of [Fe/H] = − 2.32 ± 0.01, with a residual spread of 0.3 dex, is determined for M15 using J-PLUS photometry of 664 likely cluster members.</P><P><I>Conclusions.</I> We confirm the performance of SPHINX within the ranges specified, and verify its utility as a stand-alone tool for photometric estimation of effective temperature and metallicity, and for pre-selection of metal-poor spectroscopic targets.</P>

C₂H <i>N</i> = 1 − 0 and N₂H⁺<i>J</i> = 1 − 0 observations of <i>Planck</i> Galactic cold clumps

Liu, X.-C.,Wu, Y.,Zhang, C.,Liu, T.,Yuan, J.,Qin, S.-L.,Ju, B.-G.,Li, L.-X. EDP Sciences 2019 Astronomy and astrophysics Vol.622 No.-

<P>A survey of C2H <I>N</I> = 1 − 0 and N2H<SUP>+</SUP><I>J</I> = 1 − 0 toward <I>Planck</I> Galactic cold clumps (PGCCs) was performed using the Purple Mountain Observatory’s 13.7 m telescope. C2H and N2H<SUP>+</SUP> were chosen to study the chemical evolutionary states of PGCCs. Among 121 observed molecular cores associated with PGCCs, 71 and 58 are detected with C2H <I>N</I> = 1 − 0 and N2H<SUP>+</SUP><I>J</I> = 1 − 0, respectively. The detected lines of most sources can be fitted with a single component with compatible <I>V</I>LSR and line widths, which confirms that these PGCC cores are very cold (with gas temperatures 9-21 K) and quiescent while still dominanted by turbulence. The ratio between the column densities of C2H and N2H<SUP>+</SUP> (<I>N</I>(C2H)/<I>N</I>(N2H<SUP>+</SUP>)) is found to be a good tracer for the evolutionary states of PGCC cores. Gas-grain chemical model can reproduce the decreasing trend of <I>N</I>(C2H)/<I>N</I>(N2H<SUP>+</SUP>) as a function of time. The cores with the lowest abundances of N2H<SUP>+</SUP> (<I>X</I>[N2H<SUP>+</SUP>] < 10<SUP>−10</SUP>) are the youngest, and have nearly constant abundances of C2H. In evolved cores with <I>X</I>[N2H<SUP>+</SUP>] ~10<SUP>−9</SUP>, abundances of C2H drop quickly as the exhaustion of carbon atoms. Although these PGCC cores are in different evolutionary states, they are all quite young (< 5 × 10<SUP>5</SUP> yr) with <I>N</I>(C2H) > <I>N</I>(N2H<SUP>+</SUP>). Mapping observations are carried out toward 20 PGCC cores. The PGCC cores in Cepheus have lower <I>N</I>(C2H)/<I>N</I>(N2H<SUP>+</SUP>) and larger line widths compared with those in Taurus. This implies that PGCC cores in Taurus are less chemically evolved than those in Cepheus.</P>

Structural and Temperature-Dependent Electrical/Optical Behaviors of Hot-Wall Deposited BaGa2Se4 Layers

J. J. Bang,홍광준,T. S. Jeong,C. J. Youn 한국물리학회 2018 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.73 No.1

The characteristic behavior of hot-wall deposited BaGa2Se4 layers was investigated as a function of temperature. The structural quality of the layers was found to be affected by tensile strain due to the coincidence-lattice mismatch. The carrier mobility showed an aspect of two scattering mechanisms. As the temperature was increased to 100 K, the mobility increased as a function of T1 due to impurity scattering. Also, at temperatures higher than 100 K, its behavior was reduced to two different-temperature slopes caused by lattice scattering. One was a function of T−3/2 at T > 200 K, and the other was a function of T−1/2 for 100 < T > 200 K. From the behavior of log n(T) versus 1/T, three donor-trap levels due to native defects were observed. By tracking the spectral photocurrent (PC) behavior with decreasing temperature, we found that the three PCpeak positions shifted toward shorter wavelengths and their intensities were dramatically decreased. These spectral PC peaks were due to the band-to-band transition. These band-gap variation were well matched by Eg(T) = Eg(0)−2.06×10 −3T2/(T +230.7). By the selection rule, the crystal-field and the spin-orbit splitting were found to be 0.2031 and −0.2259 eV, respectively. In the log Jph versus 1/T plot, we found that the spectral PC-intensity behavior was related to two donor-trap levels by comparing with the carrier concentration results. In conclusion, the dramatic decrease in the spectral PC intensity was attributed to trapping centers.

Characterization of Phosphoinositide-3-kinase, Class 3 (PIK3C3) Gene and Association Tests with Quantitative Traits in Pigs

Kim, J.H.,Choi, B.H.,Lim, H.T.,Park, E.W.,Lee, S.H.,Seo, B.Y.,Cho, I.C.,Lee, J.G.,Oh, S.J.,Jeon, J.T. Asian Australasian Association of Animal Productio 2005 Animal Bioscience Vol.18 No.12

This study deals with the characterization of porcine PIK3C3 and association tests with quantitative traits. PIK3C3 belongs to the class 3 PI3Ks that participate in the regulation of hepatic glucose output, glycogen synthase, and antilipolysis in typical insulin target cells such as those in the such as liver, muscle system, and fat. On the analysis of full-length mRNA sequence, the length of the PIK3C3 CDS was recorded as 2,664 bps. As well, nucleotide and amino acid identities between human and pig subjects were 92% and 99%, respectively. Five SNPs were detected over 5 exons. We performed genotyping by using a SNP C2604T on exon24 for 145 F$_2$ animals (from a cross between Korean native boars and Landrace sows) by PCR-RFLP analysis with Hpy8I used to investigate the relationship between growth and fat depot traits. In the total association analysis, which doesn' consider transmission disequilibrium, the SNP showed a significant effect (p<0.05) on body weight and carcass fat at 30 weeks of age as well as a highly significant effect (p<0.01) on back fat. In an additional sib-pair analysis, C allele still showed positive and significant effects (p<0.05) on back fat thickness and carcass fat. Moreover, the effects of C allele on the means of within-family components for carcass fat and back fat were estimated as 2.76 kg and 5.07 mm, respectively. As a result, the SNP of porcine PIK3C3 discovered in this study could be utilized as a possible genetic marker for the selection of pigs that possess low levels of back fat and carcass fat at the slaughter weight.

한국산 겨우살이 렉틴(KML-C)에 대한 단일크론항체의 생산과 특징

윤택준(T. J. Yoon),유영춘(Y. C. Yoo),강태봉(T. B. Kang),김성훈(S-H Kim),김갑수(K. S. Kim),김종배(J. B. Kim) 대한약학회 2001 약학회지 Vol.45 No.2

We have reported that water-extracted Korean mistletoe(KM-110) had various biological activities such as antitumor and immunomodulatory activity and the lectin fraction(KML-C) of the extract was one of the major factors related to its biological functions. In this paper, we produced murine monoclonal antibody(mAb) against KML-C. The mAbs obtained were largely classified into two groups according to specificity to KML-C and ML-I, a lectin from European mistletoe. One group mABs(9H7-D10 and 3C2-1H4) strongly reacted with KML-C, but not ML-I. In contrast, another group mAbs(8B11-2C5, 8E12-3E9 and 5E10-F1) reacted with both KML-C and ML-1. The subisotypes of these mAbs were shown to be IgG1(9H7-1D10, 3C2-1H4 and 8B11-2C5) or IgM(8E12-3E9 and 5E10-F1). To develop an assay system for determination of the amonunt of KML-C, we established the sandwich ELISA(enzyme-linked immunosorbent assay) method using these mAbs and horse radish peroxidase(HRP) labelled mAbs.In various combinations of the mAbs for coated antibody and detection antibody, the sandwich ELISA quantitatively detected KML-C,showing the detection limit ranging from 7-5,000ng/ml. Especially, reproducibility(C.V.) of the sandwich ELISA, in which 8E12-3E9 was used for coating antibody and 8B11-2C5-HRP for detection antibody, was 4.59-5.83 in intra assay, and 3.9-9.4 in inter assay.

채종박 품질이 이유돈의 성장에 미치는 영향

강창원,남기택,임호중,공진훈,안상태 한국축산학회 1995 한국축산학회지 Vol.37 No.4

This study was made to evaluate the nutritional values and glucosinolate contents of three types of rapeseed oil meal(RSM), originated from Canada(canola), China(CRSM:Chinese Rapeseed Oil Meal) and India (IRSM:Indian Rapeseed Oil Meal), and their dietary effects on the performance of weanling pigs. Nutritional evaluation included the contents of moisture, crude protein(CP), ether extracts (EE), crude fiber(CF), Ash, Ca and P, KOH solubility, tannin, and glucosinolate contents of each RSM. Total of two hundred-forty weanling pigs weighing about 20㎏ initially were housed in 24 pens with 10 pigs per pen. The thirty animals were assigned to one of eight rations : T₁ (0% RSM + 2% molasses), T₂ (6% canola + 2% molasses), T₃ (6% CRSM + 2% Molasses), T₄(6% IRSM + 2% molasses), T_5 (0% RSM + 5% molasses), T_6 (6% Canola + 5% molasses). T_7 (6% CRSM + 5% molasses), T_8 (6% IRSM + 5% molasses). During the experimental period, body weight and feed intakes were measured weekly and feed conversion rates were calculated. The results obtained from this experiments are summarized as follows. 1. The KOH solubility of canola, CRSM and IRSM was found to be 54.6, 35.7 and 64.8%, respectively. The glucosinolate contents of canola, CRSM and IRSM were found to be 0.11, 0.22 and 0.79%, respectively. 2. There were no significant differences between the 2% molasses and the 5% molasses supplemented groups in feed intake and body weight gain. 3. The 6% CRSM(T₃, T_7) and IRSM(T₄, T_8) groups were significantly (P$lt;0.05) inferior to the control groups(T₁, T_5) and 6% canola groups(T₂, T_6) in feed intake and body weight gains. The control groups(T₂, T_6) were significantly (P$lt;0.05) superior to the 6% canola groups(T₂, T_6), 6% CRSM(T₃, T_7) and 6% IRSM groups(T₄, T_8) in feed conversion rate.

아마씨의 급여가 착유우의 영양소 소화율 , 유생산성 및 유지방내 지방산조성에 미치는 영향

정태영(T . Y . Chung),송만강(M . K . Song),문철성(C . S . Moon),김종민(C . M . Kim),김동일(D . I . Kim),심정석(J . S . Sim) 한국영양사료학회 1996 韓國營養飼料學會誌 Vol.20 No.5

Programmed cell death ligand 1 alleviates psoriatic inflammation by suppressing IL-17A production from programmed cell death 1-high T cells

Kim, J.H.,Choi, Y.J.,Lee, B.H.,Song, M.Y.,Ban, C.Y.,Kim, J.,Park, J.,Kim, S.E.,Kim, T.G.,Park, S.H.,Kim, H.P.,Sung, Y.C.,Kim, S.C.,Shin, E.C. Mosby 2016 The journal of allergy and clinical immunology Vol.137 No.5

<P>Background: Psoriasis is one of the most common chronic inflammatory diseases of the skin. Recently, IL-17-producing T cells have been shown to play a critical role in psoriatic inflammation. Programmed cell death 1 (PD-1) is a coinhibitory receptor expressed on T cells in various chronic inflammatory diseases; however, the expression and function of PD-1 during psoriatic inflammation have not previously been characterized. Objective: We examined PD-1 expression on IL-17A-producing T cells from imiquimod-treated mice and patients with psoriasis. Additionally, we investigated the therapeutic effect of recombinant programmed cell death ligand 1 (PD-L1) protein on imiquimod-induced psoriatic inflammation. Methods: PD-1 expression on IL-17A-producing gamma delta T cells from imiquimod-treated mice was examined by means of multicolor flow cytometric analysis. In the psoriatic skin of patients, PD-1 and IL-17A expression was analyzed by using immunofluorescence. The therapeutic effect of PD-L1-Fc fusion protein (PD-L1-Fc) was assessed in imiquimod-treated mice ex vivo and in vivo. Results: During imiquimod-induced psoriatic inflammation, PD-1 is overexpressed on CD27(-)V gamma 1(-) gamma delta T cells. Furthermore, PD-1 expression on IL-17A(+) T cells was confirmed in psoriatic skin tissues from patients and imiquimod-treated mice. In the CD27(-)V gamma 1(-) gamma delta T-cell population, V gamma 4(-) gamma delta T cells with V gamma 6 mRNA expression showed a high level of PD-1 expression. Furthermore, these PD-1(hi)V gamma 4(-)(V gamma 6(+)) gamma delta Tcells were specialized for anti-CD3-induced IL-17A production, which was inhibited by PD-L1-Fc treatment. In imiquimod-treated mice PD-L1-Fc reduced psoriatic inflammation when given alone and enhanced the therapeutic effect of anti-p40 when given in combination. Conclusion: PD-1 is overexpressed in IL-17A-producing T cells in both imiquimod-treated mice and patients with psoriasis. Moreover, recombinant PD-L1-Fc alleviates psoriatic inflammation in imiquimod-treated mice.</P>