Observation of a d-wave gap in electron-doped Sr₂IrO₄

Kim, Y. K.,Sung, N. H.,Denlinger, J. D.,Kim, B. J. NATURE PUBLISHING GROUP 2016 NATURE PHYSICS Vol.12 No.1

<P>High-temperature superconductivity in cuprates emerges out of a highly enigmatic 'pseudogap' metal phase. The mechanism of high-temperature superconductivity is probably encrypted in the elusive relationship between the two phases, which spectroscopically is manifested as Fermi arcs-disconnected segments of zero-energy states-collapsing into d-wave point nodes upon entering the superconducting phase. Here, we reproduce this distinct cuprate phenomenology in the 5d transition-metal oxide Sr2IrO4. Using angle-resolved photo-emission, we show that the clean, low-temperature phase of 6-8% electron-doped Sr2IrO4 has gapless excitations only at four isolated points in the Brillouin zone, with a predominant d-wave symmetry of the gap. Our work thus establishes a connection between the low-temperature d-wave instability and the previously reported high-temperature Fermi arcs in electron-doped Sr2IrO4 (ref. 1). Although the physical origin of the d-wave gap remains to be understood, Sr2IrO4 is the first non-cuprate material to spectroscopically reproduce the complete phenomenology of the cuprates, thus offering a new material platform to investigate the relationship between the pseudogap and the d-wave gap.</P>

Limiting Concentrate during Growing Period Affect Performance and Gene Expression of Hepatic Gluconeogenic Enzymes and Visfatin in Korean Native Beef Calves

Chang, S.S.,Lohakare, J.D.,Singh, N.K.,Kwon, E.G.,Nejad, J.G.,Sung, K.I.,Hong, S.K. Asian Australasian Association of Animal Productio 2013 Animal Bioscience Vol.26 No.2

This study elucidated the effects of limited concentrate feeding on growth, plasma profile, and gene expression of gluconeogenic enzymes and visfatin in the liver of Hanwoo beef calves. The purpose of this study was to test that reducing the amount of concentrate would partially be compensated by increasing the intake of forage and by altering the metabolic status. The study utilized 20 Korean native beef calves (Hanwoo; 60 to 70 d of age) divided into two groups of 10 calves each for 158 d. Control group calves received the amount of concentrate as per the established Korean feeding standards for Hanwoo, whereas calves in the restricted group only received half the amount of concentrate as per standard requirements. Good quality forage (Timothy hay) was available for ad libitum consumption to both groups. Since calves were with their dam until 4 months of age in breeding pens before weaning, the intake of milk before weaning was not recorded, however, the concentrate and forage intakes were recorded daily. Body weights (BW) were recorded at start and on 10 d interval. Blood samples were collected at start and at 50 d interval. On the final day of the experiment, liver biopsies were collected from all animals in each group. The BW was not different between the groups at all times, but tended to be higher (p = 0.061) only at final BW in control than restricted group. Total BW gain in the control group was 116.2 kg as opposed to 84.1 kg in restricted group that led to average BW gain of 736 g/d and 532 g/d in respective groups, and the differences were significant (p<0.01). As planned, the calves in the control group had higher concentrate and lower forage intake than the restricted group. The plasma variables like total protein and urea were higher (p<0.05) in control than restricted group. The mRNA expressions for the gluconeogenic enzymes such as cytosolic phosphoenol pyruvate carboxykinase (EC 4.1.1.32) and pyruvate carboxylase (EC 6.4.1.1), and visfatin measured by quantitative real-time PCR in liver biopsies showed higher expression (p<0.05) in restricted group than control. Overall, restricting concentrate severely reduced the growth intensity and affected few plasma indices, and gene expression in liver was increased indicating that restricting concentrate in the feeding schemes during early growth for beef calves is not advocated.

2005학년도 부산교육대학교 신입생 입학전형 방안

성병창,이경애,백대현 부산교육대학교 초등교육연구소 2004 초등교육연구 Vol.19 No.-

The goal of this paper is to develop a plan for the 2005 BNUE's annual regular recruitment. We develop a plan in which BNUE seeks to maximize the quality of prospective students based on the main issues in relation to 7th curriculum and the College Scholastic Ability Test (CSAT). We deduce the following three suggestions regarding to reflect the CAST score. (ⅰ) BNUE reflects the standard scores of Verbal (Korean) by 27% of the CSAT and Foreign Language (English) by 26% of the CSAT. (ⅱ) BNUE reflects the standard score of Mathematics by 27% of the CSAT, but by adding at least an additional 5.5% of the mathematics standard score if Mathematics type 'Ga' is taken instead of type 'Na'. (ⅲ) BNUE reflects the best three (two in case of Occupational Inquiry) standard scores of Inquiry score by 20% of the CSAT by choosing higher standard score if subjects' ranking percentages are equal.

녹용분말 급여가 성장기별 흰쥐의 성장 및 장기발육에 미치는 효과

성하균,김동균,신형태 한국동물자원과학회 2003 한국축산학회지 Vol.45 No.5

The velvet antler of Korean sika deer has been used to the important resources for human health care with ginseng in Korea and Chinese. For studying on biological function of deer velvet being recorded in many ancient literatures, this experiment was conducted to evaluate the effects of powdered velvet antler on growth, feed intake, feed efficiency and intestinal organ development in growing and adult Sprague-Dawley Rats. Experiments were designed by adding amount of powdered velvet antler such as control (non-supplementation), powdered velvet antler Ⅰ (PVA Ⅰ, recommended dos) and powdered velvet antler Ⅱ (PVA Ⅱ, thrice recommended dose). The recommended dose of powdered velvet in this experiment was calculated with metabolic body weight of rats, which based on the recommended amounts for 70㎏ of human. The growths of growing and adult rats generally appeared advantage in PVA supplementation. The final body weight of control, PVA Ⅰ and Ⅱ were respectively 470±39.00g, 478±3033g and 475±22.72g in growing rats, and 485±38.50g, 521±38.67g and 508±34.44g in adult rats. The average daily feed intake were not significantly influenced but the feed efficiency ratios (feed/gain) were improved by PVA supplementation. The feed/gain ratios of control, PVA Ⅰ and Ⅱ were respectively 5.99, 5.47 and 5.54 in growing rats, and 9.04m 7.73 and 8.18 in adult rats. In case of developments of liver, heart, kidney and stomach, we obtained favorable results in both PAC Ⅰ and Ⅱ, but their results were not significantly different according to amount of PVA supplementation. Because liver and heart are important organs in the circulation of blood, their favorable effects suggest that velvet antler may have factors contributing hematopoiesis. Conclusively, supplementation of that velvet antler may have factors contributing hematopoiesis. Conclusively, supplementation of powdered velvet antler resulted in an improved growth, feed efficiency and development of some intestinal organs in growing and adult rat. Even if further investigation of dose in human health care are should be performed, this experiment appeared the best desirable results in PVA Ⅰ, recommended dose of powdered velvet antler.

산란계의 연령과 면역주기에 따른 난황 중의 Streptococcus mutans 특이 항체 함량

성기승,김영붕,노정해,이남형,한찬규,손동화 한국축산학회 1999 한국축산학회지 Vol.41 No.5

Streptococcus mutans-specific IgY content change, laying rate, egg weight and weight change were measured for 17-week and 30-week old hens. Vaccinations with Streptococcus mutans were made two times(eight week interval), three times(four week interval) and five times(two week interval), respectively. It was observed that the laying rate of vaccinated hens was likely lower than that of non-vaccinated group. No effect on body weight by vaccination was found out. Egg weight did not show a certain tendency by vaccination. Anti-S. mutans IgY started to be detected two weeks after the lst vaccination for 30-week old hens. It was not detected for non-vaccinated group. The antibody activity was consistently detected after 8 weeks from the last vaccination. The measurement of total IgY and S. mutans-specific IgY in the egges from vaccinated hens revealed that IgY tended to increase with the number of vaccination. S. mutans-specific IgY content of five-time vaccinated l7-week hens was much higher than that of 30-week old hens. To obtain steady amount of specific IgY, multiple vaccination with two week interval was recommended.

한국 토종닭고기의 숙성중 부위별 근원섬유 단백질의 변화

성삼경,안동현,권연주,박소연 한국축산학회 1997 한국축산학회지 Vol.39 No.5

Postmortem changes were examined in myofibrillar proteins of M. pectoralis, M. sartorius and M. soleus from Korean native chickens(KNC) and commercial broilers. Purified myofibrils were prepared from the muscles after 0, 3, 6, 12, 24, 48, 72 and 120 hours of post mortem storage at 4℃. SDS-PAGE results showed that 30kDa and 32kDa components appeared earlier in the M. pectoralis than in the M. sartorius and M. coleus from KNC and broilers. These components were observed after 12 hours post mortem in all M. pectoralis. Titin I disappeared after 12 hours post mortem in M. pectoralis from KNC, earlier than that of broilers. In M. sartorius, thin II appeared after 6 hours post mortem in KNC, earlier than that of broilers, and thin I disappeared after 120 hours of storage. Titin II appeared after 24 hours post mortem in M. Soleus from KNC and broilers. Among all the samples studied, the post mortem changes in M. Pectoralis was the fastest and those changes in M. coleus was the slowest. The molecular weight of the titin in M. coleus and M. sartorius is larger than that of M. pectoralis from KNC.

재래산양 락토페린 유전자 5' Flanking 영역의 특성에 관한 연구

상병찬,유대열,유성란,이태훈,신상태,이경광 한국축산학회 2000 한국축산학회지 Vol.42 No.1

Lactoferrin(Lf), a ferric ion(Fe^(3+))-binding glycoprotein, is found most notably in milk and some exocrine secretions. It is a main antimicrobial component of colostrum and milk that contributes to protection of the infant against infectious diseases. To analyze 5' flanking region of Korean native goat lactoferrin gene, we cloned and sequenced 975 by of 5' flanking region of Korean native goat Lf gene. When compared to those of bovine and human Lf, the nucleotide sequences exhibited about 90.9% and 49.7% homology, respectively. The transcription start site was localized by primer extension to residue C, which is 38 nucleotides upstream from the ATG start codon. The 5' flanking region of Korean native goat lactoferrin gene contains putative transcription factor binding sites such as SP1, CAT, C/EBP and GATA-1.

A Single-Flux-Quantum Shift Register based on High-$T_c$ Superconducting Step-edge Josephson Junctions

Sung G.Y.,Choi, C.H.,Suh J.D.,Han, S. K.,Kang, K.Y.,Hwang, J.S.,Yoon, S.G.,Jung, K.R.,Lee, Y.H.,Kang, J.H.,Kim, Y.H.,Hahn, T.S. The Korean Superconductivity Society 1999 Progress in superconductivity Vol.1 No.1

We have fabricated and tested a simple circuit of the rapid single-flux-quantum(RSFQ) four-stage shift register using a single layer high-$T_c$ superconducting (HTS) $YBa_2Cu_3O_{7-x}$ (YBCO) thin film structure with 9 step-edge Josephson junctions. The circuit includes two read superconducting quantum interference devices(SQUID) and four stages. To establish a robust HTS RSFQ device fabrication process, we have focussed on the reproducible process of sharp and straight step-edge formation as well as the ratio of film thickness to step height, t/h. The spread of step-edge junction parameters was measured from each 13 junctions with t/h=1/3, 1/2, and 2/3 at various temperatures. We have demonstrated the simplified operation of the shift register at 65 K.

우리나라 製絲用水의 實態 調査

成載千,李鍍,李道洙,高春燮,崔金植,胄元煥 한국잠사학회 1987 한국잠사곤충학회지 Vol.29 No.2

This investigaton was carried cut to obtain the reeling water conditions in Korea. The analyzed items of water were pH, colority, turbidity, acidity, alkalinity, solids electric conductibity hardness and heavy metal ions. About 40% of the reeling water were found to be agreeable, 30% were acceptable provided with some quality control and the others were out of acceptable range mainly based on the M-alkalinity, acidity, pH and total hardness. It was found that there was a following relationship between total hardness and electric conductibity with the relative correlation coefficient r=0.9145. y = 15.967 + 0.22774x Where x, y are electric conductivity and total hardness respectively.

Intriguing Magnetoresistance Behaviors of Epitaxial SrRuO3 Thin Films

K. D. Sung,정종훈,허남정,Y. A. Park 한국물리학회 2008 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.52 No.6

We have investigated the magnetoresistance of epitaxial SrRuO₃ thin films grown on SrTiO₃ substrates by using pulsed laser deposition. The negative magnetoresistance curves of SrRuO$_{3}$ thin films typically show two maxima, one near Tc ~ 150 K and the other near T* ~ 30 K. As the grain size and/or the crystalline quality of the films decreases, the negative magnetoresistance value decreases without changing the peak near Tc while the peak near T* moves to lower temperature and then finally disappears. We explain these intriguing behaviors near T* in conjunction with the magnetic domain rotation over magneto-crystalline anisotropy, which is significantly modified by the quality of the films.