Ferromagnetic Order in Rapidly Cooled Nd-Fe-Co-Al Alloy Ribbons

Phan, T. L.,Zhang, Y. D.,Dan, N. H.,Thang, D. D.,Thanh, T. D.,Zhang, P.,Yu, S. C. IEEE 2013 IEEE transactions on magnetics Vol.49 No.7

<P>We have studied the magnetic properties of Nd<SUB>45</SUB>Fe<SUB>30</SUB>Co<SUB>15</SUB>Al<SUB>10</SUB> alloy ribbons with various thicknesses of about 120 (N<SUB>1</SUB>) and 50 μm (N<SUB>2</SUB>) prepared by melt-spinning. Structural analyses based on an X-ray diffractometer and a high-resolution transmission electron microscope revealed an existence of nanocrystals with sizes of 10 ~ 20 nm surrounded by an amorphous host matrix. With decreasing ribbon thickness and nanocrystalline size, magnetic studies upon a vibrating sample magnetometer indicated the decrease of the Curie temperature (T<SUB>C</SUB>), coercive force (H<SUB>c</SUB>), and magnetic entropy change (ΔS<SUB>m</SUB>). In the ferromagnetic region, however, magnetization values determined for N<SUB>2</SUB> are greater than those determined for N<SUB>1</SUB>. These results are related to the differences in the critical exponents of N<SUB>1</SUB> (β=0.418 and γ=1.173), and N<SUB>2</SUB> (β=0.512 and γ=1.077), which are characteristic for the ferromagnetic nature existing in the alloy ribbons with different thicknesses.</P>

Nitrogen-Doped Carbon Nanoparticles by Flame Synthesis as Anode Material for Rechargeable Lithium-Ion Batteries

Bhattacharjya, Dhrubajyoti,Park, Hyean-Yeol,Kim, Min-Sik,Choi, Hyuck-Soo,Inamdar, Shaukatali N.,Yu, Jong-Sung American Chemical Society 2014 Langmuir Vol.30 No.1

<P>Nitrogen-doped turbostratic carbon nanoparticles (NPs) are prepared using fast single-step flame synthesis by directly burning acetonitrile in air atmosphere and investigated as an anode material for lithium-ion batteries. The as-prepared N-doped carbon NPs show excellent Li-ion stoarage properties with initial discharge capacity of 596 mA h g<SUP>–1</SUP>, which is 17% more than that shown by the corresponding undoped carbon NPs synthesized by identical process with acetone as carbon precursor and also much higher than that of commercial graphite anode. Further analysis shows that the charge–discharge process of N-doped carbon is highly stable and reversible not only at high current density but also over 100 cycles, retaining 71% of initial discharge capacity. Electrochemical impedance spectroscopy also shows that N-doped carbon has better conductivity for charge and ions than that of undoped carbon. The high specific capacity and very stable cyclic performance are attributed to large number of turbostratic defects and N and associated increased O content in the flame-synthesized N-doped carbon. To the best of our knowledge, this is the first report which demonstrates single-step, direct flame synthesis of N-doped turbostratic carbon NPs and their application as a potential anode material with high capacity and superior battery performance. The method is extremely simple, low cost, energy efficient, very effective, and can be easily scaled up for large scale production.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/langd5/2014/langd5.2014.30.issue-1/la403366e/production/images/medium/la-2013-03366e_0006.gif'></P>

Relationship between the tertiary structures of mastoparan B and its analogs and their lytic activities studied by NMR spectroscopy

Yu, K.,Kang, S.,Park, N.,Shin, J.,Kim, Yangmee 부산대학교 유전공학연구소 2000 분자생물학 연구보 Vol.16 No.-

Mastoparan B (MP-B), an antimicrobial cationic tetradecapeptide amide isolated from the venom of the hornet Vespa basalis, is an amphiphilic x-helical peptide. MP-B possesses a mariety of biological activities, such as mast cells degradation histamine release, erythrocyte lysis and inhibition of the growth of Gram-positive and Gram-negative bacteria. In order to study the relationship between the structure and the biological activity of MP-B, we used four analogs by replacing amino acids with alanine. Tertiary structures of MP-B and its analogs in 2,2,2-trifluoroethanol (TFE)-containing aqueous solution have been determined by NMR spectroscopy and molecular modeling. The results indicate that [Ala^4]MP-B and [Ala^12]MP-B with higher hydrophobicity adopt a higher content of amphiphilic helical structures, and have better antimicrobial and hemolytic activities than MP-B. However, [Ala^3]MP-B and [Ala^9]MP-B and hydrophobicity have disordered structures. [Ala^3]MP-B and [Ala^9]MP-B have low antimicrobial activity and much less hemolytic activity relative to MP-B. It is likely that tryptophan residue in MP-B and appropriate hydrophobicity of MP-B to induce x-helical structure is essential for the antibacterial and hemolytic activity of MP-B. This study can aid understanding of the structure-activity relationship of MP-B and to design peptides to possess lytic activity.

An animal model of obstructive sleep apnea in rabbit

Yu, M. S.,Jung, N. R.,Choi, K. H.,Choi, K.,Lee, B. J.,Chung, Y. S. LARYNGOSCOPE 2014 The Laryngoscope Vol.124 No.3

Objectives/HypothesisAn animal model of obstructive sleep apnea (OSA) may help to investigate the pathophysiology of this disorder and develop appropriate treatments. We investigated the feasibility of a rabbit model of OSA.Study DesignAnimal study.MethodsTwelve New Zealand white rabbits were injected at the base of their tongues under endoscopic guidance with liquid silicone (experimental group, n=6) or normal saline (control group, n=6). Polysomnography was performed before and after injection. The development of OSA and changes in sleep parameters were compared between the two groups.ResultsBefore injection, all rabbits showed normal breathing during sleep without hypopnea. In the silicone group, the rabbits had a mean of 29.96.9 hypopneas/hour and a mean of 10.43.1 apneas/hour 1 month after silicone injection and 28.4 +/- 6.9 hypopneas/hour and 10.0 +/- 3.3 apneas/hour 3 months after silicone injection (P<0.05). Mean total sleep time decreased from 260.3 +/- 70.2 minutes at baseline to 152.5 +/- 38.8 minutes 1 month and 206.8 +/- 60.3 minutes 3 months after injection, with a decrease in stage II sleep. In the saline group, however, there were no breathing events during sleep.ConclusionsThese results show that silicone injections into the tongue base of rabbits can result in OSA.Level of EvidenceN/A Laryngoscope, 124:789-796, 2014

Embryo Survival on Day 25 of Generation in the Gilt is Not Affected by Exogenous Progesterone but is Correlated with Levels of Insulin-Like Growth Factor-I (IGF-I) mRNA in the Uterus

Yu, Z.,Gordon, J.R.,Kirkwood, R.N.,Thacker, P.A. Asian Australasian Association of Animal Productio 1999 Animal Bioscience Vol.12 No.6

The present study was undertaken to determine the effect of administration of exogenous progesterone early in gestation on uterine levels of IGF-I mRNA and on embryo survival at day 25 of gestation in the pig. Forty-one prepubertal gilts were induced into oestrus with PG600 and artificially inseminated at their subsequent naturally occurring oestrus. Gilts were then randomly assigned to one of three groups. Gilts in the two treatment groups were injected intramuscularly with 50 mg of progesterone either from day 2 to 14 (N=14) or from day 4 to 14 (N=15) after breeding while those in the control group (N=12) were given corn oil (0.5 ml) from day 2 to 14. Between days 25 and 28 of gestation, gilts were slaughtered and reproductive tracts were recovered. Endometrial tissue (1 g) was collected and analysed for IGF-I mRNA levels using a reverse transcription-polymerase chain reaction, Progesterone treatment, starting either on day 2 or 4 after breeding, neither significantly increased embryo survival rate by day 25 of gestation nor altered IGF-I mRNA levels in uterine tissue. However, across all samples, the IGF-I mRNA level in the uterus was highly correlated with embryo survival rate (r=0.8193, p<0.01), supporting the involvement of IGF-I in the regulation of porcine embryo development.

NEUTRON FIELD OF THE EARTH, ORIGIN AND DYNAMICS

Kuzhevshkij, B.M.,Nechaev, O.Yu.,Panasyuk, M.I.,Sigaeva, E.A.,Volodichev, N.N.,Zakharov, V.A. 대한방사선 방어학회 2001 방사선방어학회지 Vol.26 No.3

It is shown, that both cosmic radiation (external source) and natural radioactive gases (inner source) are sources of neutrons near the Earth crust. Correlation between the Earth crust dynamics and variations of thermal and slow neutron flux near the Earth surface is studied. It is shown, that variations of neutron flux near the Earth crust can be used for short-term predicting of natural hazards.

Salinomycin induces endoplasmic reticulum stress-mediated autophagy and apoptosis through generation of reactive oxygen species in human glioma U87MG cells

Yu, S.-N.,Kim, S.-H.,Kim, K.-Y.,Ji, J.-H.,Seo, Y.-K.,Yu, H. S.,Ahn, S.-C. Spandidos Publications 2017 ONCOLOGY REPORTS Vol.37 No.6

<P>Salinomycin is a polyether ionophore antibiotic that has recently been shown to induce cell apoptosis in human cancer cells displaying multiple mechanisms of drug resistance. In the present study, we explored the impact of salinomycin on the apoptosis and autophagy as well as the correlation between those effects and endoplasmic reticulum (ER) stress molecular mechanisms in human glioma U87MG cells. Apoptosis, autophagy and reactive oxygen species (ROS) were analyzed using flow cytometry. In addition, expression levels of apoptosis-, autophagy- and ER stress-related proteins were determined by western blotting. The results showed that salinomycin induced apoptosis, ER stress and autophagy in glioma cancer cell lines. In addition, salinomycin also induced ROS generation, and the ROS scavenger N-acetyl-L-cysteine was found to inhibit the salinomycin-induced apoptosis, ER stress and autophagy. The inhibition of ER stress with 4-phenylbutyric acid depressed salinomycin-induced apoptosis and autophagy. Salinomycin increased the expression of autophagy marker protein, LC3B, and accumulation of acidic vesicular organelles. Furthermore, pre-treatment with the autophagy inhibitor 3-methyladenine showed potential in increasing the apoptosis rate induced by salinomycin in the U87MG cells. Taken together, these results revealed that salinomycin induced apoptosis and autophagy via ER stress mediated by ROS, suggesting that ER stress by salinomycin plays a dual function in both promoting and suppressing cell death.</P>

PREDICTION OF WEAR OF RUBBING BODIES ON THE BASE OF A THEORETICAL-INVARIANT METHOD

Drozdov, Yu. N.,Ignatieva, Z.V. ENGINEERING TRIBOLOGY RESEARCH INSTITUTE KYUNGPOOK 2000 INTERNATIONAL SYMPOSIUM ON HIGH PERFORMANCE OF TRI Vol.2000 No.-

A theoretical-invariant method of friction units service life prediction is developed based on the combining some deterministic and probabilistic approaches to the problem of surface failure taking into consideration a number of mechanical, physico-chemical, thermal aspects of contact interaction of rubbing bodies.

THE BLUE STAIN FUNGI IN LIVING CONIFERS

(N . V . Pashenova),(V . P . Vetrova),(E . N . Aphanasova),(M . Yu Konstantinov) 한국목재공학회 2000 한국목재공학회 학술발표논문집 Vol.2000 No.-

N/A

Lipid N-formylation Occurs During Fixation with Formalin

김민식,Min Jung Kim,임희진,Muwoong Kim,Yu Ri Choi,Thy N. C. Nguyen,Seung Cheol Park,Kwang Pyo Kim,Junyang Jung 사단법인 한국질량분석학회 2022 Mass spectrometry letters Vol.13 No.2

Human tissues and organs can be preserved intact by fixation with formalin for the future analysis of biomolecules of interest. With the advances in high-throughput methods, numerous protocols have been developed and optimized to attain the most pathophysiological information out of biomolecules, including RNA and proteins, in formalin-fixed samples. However, there is no systematic study to examine the effects of formalin fixation on the lipidome of biological samples in a global fashion. In this study, we conducted a mass spectrometry-based analysis to survey the alteration in the lipidome of mice brains by fixation methods. A total of 308 lipids were quantitatively measured using triple quadrupole mass spectrometry. We found that most were unchanged after formalin fixation except for a few lipid classes such as phosphatidylethanolamine.