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2.
Tissue Antigens ; 85(2): 138-9, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25565060

RESUMEN

The new allele, DRB1*04:10:03, showed one nucleotide difference with DRB1*04:10:01 (705C>T).


Asunto(s)
Alelos , Cadenas HLA-DRB1/genética , Secuencia de Bases , Exones/genética , Humanos , Datos de Secuencia Molecular , Alineación de Secuencia
4.
Tissue Antigens ; 83(4): 291-2, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24571579

RESUMEN

The new allele A*02:465 showed one nucleotide difference with A*02:06:01 (172G>A).


Asunto(s)
Alelos , Bases de Datos de Ácidos Nucleicos , Antígeno HLA-A2/genética , Adulto , Secuencia de Bases , Humanos , Corea (Geográfico) , Masculino , Datos de Secuencia Molecular
5.
Nat Mater ; 10(5): 347-51, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21399629

RESUMEN

A spin valve is a microelectronic device in which high- and low-resistance states are realized by using both the charge and spin of carriers. Spin-valve structures used in modern hard-drive read heads and magnetic random access memoriescomprise two ferromagnetic electrodes whose relative magnetization orientations can be switched between parallel and antiparallel configurations, yielding the desired giant or tunnelling magnetoresistance effect. Here we demonstrate more than 100% spin-valve-like signal in a NiFe/IrMn/MgO/Pt stack with an antiferromagnet on one side and a non-magnetic metal on the other side of the tunnel barrier. Ferromagneticmoments in NiFe are reversed by external fields of approximately 50 mT or less, and the exchange-spring effect of NiFe on IrMn induces rotation of antiferromagnetic moments in IrMn, which is detected by the measured tunnelling anisotropic magnetoresistance. Our work demonstrates a spintronic element whose transport characteristics are governed by an antiferromagnet. It demonstrates that sensitivity to low magnetic fields can be combined with large, spin-orbit-coupling-induced magnetotransport anisotropy using a single magnetic electrode. The antiferromagnetic tunnelling anisotropic magnetoresistance provides a means to study magnetic characteristics of antiferromagnetic films by an electronic-transport measurement.

6.
Phys Rev Lett ; 108(1): 017201, 2012 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-22304281

RESUMEN

We employ antiferromagnetic tunneling anisotropic magnetoresistance to study the behavior of antiferromagnetically ordered moments in IrMn exchange coupled to NiFe. Experiments performed by common laboratory tools for magnetization and electrical transport measurements allow us to directly link the broadening of the NiFe hysteresis loop and its shift (exchange bias) to the rotation and pinning of antiferromagnetic moments in IrMn. At higher temperatures, the broadened loops show zero shift, which correlates with the observation of fully rotating antiferromagnetic moments inside the IrMn film. The onset of exchange bias at lower temperatures is linked to a partial rotation between distinct metastable states and pinning of the IrMn antiferromagnetic moments in these states. The observation complements common pictures of exchange bias and reveals an electrically measurable memory effect in an antiferromagnet.

7.
Phys Rev Lett ; 103(20): 207202, 2009 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-20366006

RESUMEN

We investigated the orbital anisotropy of LuFe(2)O(4) using the Fe L(2,3)- and O K-edge x-ray absorption spectroscopy (XAS) and cluster model calculations. X-ray magnetic circular dichroism reveals a surprisingly large orbital magnetic moment (m(o) approximately 0.8 micro(B)/f.u.), which originates the giant magnetic anisotropy. The polarization dependent XAS enables us to identify the orbital states and occupations, different from the band calculation predictions. These findings were examined by using the cluster model analysis, which also explains the orbital magnetic moment as well as the total moment (2.9 micro(B)/f.u.). Taking into account the charge order, we also determined the spin structure.

8.
HLA ; 91(4): 293-294, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29451370

RESUMEN

Three novel HLA alleles, HLA-A*26:118, DQB1*02:65 and DPB1*05:01:07, were identified and confirmed by monoallelic sequencing.


Asunto(s)
Alelos , Pueblo Asiatico/genética , Antígenos HLA-A/genética , Cadenas beta de HLA-DP/genética , Cadenas beta de HLA-DQ/genética , Secuencia de Bases , Humanos , Alineación de Secuencia
10.
HLA ; 91(4): 306-307, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29394008

RESUMEN

The new allele HLA-C*03:03:35 showed one nucleotide difference with C*03:03:01:01 at position 408 (G>T).


Asunto(s)
Alelos , Antígenos HLA-C/genética , Secuencia de Bases , Exones/genética , Sitios Genéticos , Prueba de Histocompatibilidad , Humanos , Alineación de Secuencia
11.
HLA ; 91(4): 312-313, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29388734

RESUMEN

HLA-DQB1*04:01:05 differs from DQB1*04:01:01 by a single nucleotide substitution at codon 30 (TAC>TAT).


Asunto(s)
Alelos , Pueblo Asiatico/genética , Cadenas beta de HLA-DQ/genética , Secuencia de Bases , Exones/genética , Prueba de Histocompatibilidad , Humanos , Alineación de Secuencia
14.
Sci Rep ; 6: 35471, 2016 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-27762278

RESUMEN

Antiferromagnetic spintronics is an emerging field; antiferromagnets can improve the functionalities of ferromagnets with higher response times, and having the information shielded against external magnetic field. Moreover, a large list of aniferromagnetic semiconductors and metals with Néel temperatures above room temperature exists. In the present manuscript, we persevere in the quest for the limits of how large can anisotropic magnetoresistance be in antiferromagnetic materials with very large spin-orbit coupling. We selected IrMn as a prime example of first-class moment (Mn) and spin-orbit (Ir) combination. Isothermal magnetotransport measurements in an antiferromagnetic-metal(IrMn)/ferromagnetic-insulator thin film bilayer have been performed. The metal/insulator structure with magnetic coupling between both layers allows the measurement of the modulation of the transport properties exclusively in the antiferromagnetic layer. Anisotropic magnetoresistance as large as 0.15% has been found, which is much larger than that for a bare IrMn layer. Interestingly, it has been observed that anisotropic magnetoresistance is strongly influenced by the field cooling conditions, signaling the dependence of the found response on the formation of domains at the magnetic ordering temperature.

15.
Water Sci Technol ; 52(10-11): 325-34, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16459807

RESUMEN

Wastewater discharge from coal refining plants contains a number of biologically toxic compounds; 2000-2500 mg/l of COD of which 40% is composed of phenol, 100-400 mg/l of thiocyanate, 10-40 mg/l of cyanide, 100-250 mg/l of NH4+-N and 150-300 mg/l of total nitrogen. In order to treat this kind of high strength wastewater, we have developed a high performance biofilm process using fluidizing bio-carriers of the tube chip type. The fluidizing biofilm carriers are made of a composite of polyethylene and several inorganic materials, whose density is controlled at 0.97-0.98 g/ml. The fluidizing biofilm carriers show sound fluidization characteristics inside bioreactors. The wastewater is treated using three consecutive series reactors in oxic-anoxic-oxic arrangement. Each reactor is charged with the fluidizing biofilm carriers of 50 vol%. Furthermore, newly cultured active microorganisms for the thiocyanate biodegradation are added in the biofilm process. At total hydraulic retention time of 2.2 days, this process can achieve steady state removal efficiencies: COD, 99%; thiocyanate, 99%; NH4+-N, 99% and total nitrogen, 90%.


Asunto(s)
Reactores Biológicos , Cianuros/aislamiento & purificación , Residuos Industriales , Nitrógeno/aislamiento & purificación , Aguas del Alcantarillado/microbiología , Tiocianatos/aislamiento & purificación , Eliminación de Residuos Líquidos/métodos , Aerobiosis , Biopelículas , Carbono/aislamiento & purificación , Carbón Mineral , Oxígeno/química , Oxígeno/aislamiento & purificación , Oxígeno/metabolismo , Polietileno/química , Aguas del Alcantarillado/química , Factores de Tiempo
16.
Biotechnol Prog ; 16(2): 302-4, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10753460

RESUMEN

Continuous culture for the production of ethanol from wood hydrolysate was carried out in an internal membrane-filtration bioreactor. The hydrolysate medium was sterilized at a relatively low temperature of 60 degrees C with the intention of reducing the formation of inhibitory compounds during the sterilization. The maximum ethanol concentration and productivity obtained in this study were 76.9 g/L and 16.9 g/L-h, respectively, which were much higher than those (57.2-67 g/L and 0.3-1.0 g/L-h) obtained in batch cultures using hydrolysate media sterilized at 60 degrees C. The productivity was also found to be much higher than that (6.7 g/L-h) obtained in a continuous cell retention culture using a wood hydrolysate sterilized at 121 degrees C. These results show that the internal membrane-filtration bioreactor in combination with low-temperature sterilization could be very effective for ethanol production from wood hydrolysate.


Asunto(s)
Reactores Biológicos , Etanol/metabolismo , Filtración/métodos , Hidrólisis , Membranas Artificiales , Saccharomyces cerevisiae , Esterilización , Temperatura , Madera
17.
Yonsei Med J ; 37(1): 38-46, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8967108

RESUMEN

To elucidate the Ca2+ release mechanisms in the rabbit coronary artery, arterial preparations were permeabilized with beta-escin and changes in tension were measured under varying experimental conditions. Additionally, we investigated properties and distribution of two kinds of Ca2+ release mechanisms, Ca2+-induced Ca2+ release (CICR) and IP3-induced Ca2+ release (IICR). The results obtained were summarized as follows; 1. When a rabbit coronary artery was incubated in a relaxing solution containing 30 microM beta-escin for 40 min. sensitivity to externally added Ca2+ was much higher in beta-escin permeabilized muscle than in intact preparations. The contractile effect of IP3 in beta-escin permeabilized muscle was also demonstrated; 2. Caffeine and IP3 contracted coronary arteries were permeabilized with beta-escin, but the amplitude of contraction was much larger in the presence of caffeine than of IP3. 3. Intracellular heparin completely inhibited the contractions induced by IP3, but not those by caffeine. On the other hand, procaine inhibited the responses to caffeine, but not those to IP3. Ryanodine inhibited both the caffeine- and IP3-induced contractions. 4. The amplitude of contractile responses was much larger to the maximal stimulation of CICR by applying caffeine than to the maximal stimulation of IICR by applying IP3. After the maximal CICR stimulation by caffeine, the activation of IICR by IP3 without the reloading of Ca2+ could no longer evoke contraction. On the other hand, after the maximal IICR activation, the activation of CICR could still evoke contraction although the amplitude of the contraction was smaller when compared with the case without the initial IICR stimulation. 5. Acetylcholine contracted coronary artery smooth muscles were permeabilized with beta-escin. However, in the absence of added guanosine triphosphate (GTP), the responses were very small. Acetylcholine-induced contraction was inhibited by heparin, but not by procaine. From the above results, it may be concluded that there are two kinds of mechanisms of Ca2+ release, CICR and IICR, in the rabbit coronary artery smooth muscle cell. Also, whereas the CICR mechanism distributes on the membrane of the whole smooth muscle Ca2+ store, the IICR mechanism distributes only on a part of it.


Asunto(s)
Calcio/metabolismo , Vasos Coronarios/metabolismo , Membranas Intracelulares/metabolismo , Animales , Arterias/metabolismo , Permeabilidad Capilar/efectos de los fármacos , Vasos Coronarios/efectos de los fármacos , Escina/farmacología , Técnicas In Vitro , Conejos , Distribución Tisular
18.
Artículo en Inglés | MEDLINE | ID: mdl-24109729

RESUMEN

To obtain real-time dose information in photon-beam therapy using a clinical linear accelerator, we fabricated a novel Cerenkov fiber-optic dosimeter using two plastic optical fibers without employing a scintillator. In this study, the light intensity and spectrum of Cerenkov radiation induced by a high-energy photon beam were measured as functions of the irradiation angle and the length difference between the two plastic optical fibers in the dosimeter probe. Also, we obtained a percentage depth dose curve for a 6 MV photon beam with a field size of 10 × 10 cm(2) according to the depth of the solid water phantom. Based on the results of this study, it is anticipated that the proposed Cerenkov fiber-optic dosimeter can be developed as a useful dosimeter to accurately obtain dose information prior to conducting radiotherapy.


Asunto(s)
Radioterapia/instrumentación , Estudios de Factibilidad , Tecnología de Fibra Óptica , Humanos , Fibras Ópticas , Fantasmas de Imagen , Radiometría/instrumentación
19.
Phys Rev Lett ; 100(8): 087204, 2008 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-18352660

RESUMEN

We report observations of tunneling anisotropic magnetoresitance (TAMR) in vertical tunnel devices with a ferromagnetic multilayer-(Co/Pt) electrode and a nonmagnetic Pt counterelectrode separated by an AlOx barrier. In stacks with the ferromagnetic electrode terminated by a Co film the TAMR magnitude saturates at 0.15% beyond which it shows only weak dependence on the magnetic field strength, bias voltage, and temperature. For ferromagnetic electrodes terminated by two monolayers of Pt we observe order(s) of magnitude enhancement of the TAMR and a strong dependence on field, temperature and bias. The discussion of experiments is based on relativistic ab initio calculations of magnetization orientation dependent densities of states of Co and Co/Pt model systems.

20.
Phys Rev Lett ; 101(7): 076402, 2008 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-18764560

RESUMEN

We investigated the electronic structure of 5d transition-metal oxide Sr2IrO4 using angle-resolved photoemission, optical conductivity, x-ray absorption measurements, and first-principles band calculations. The system was found to be well described by novel effective total angular momentum Jeff states, in which the relativistic spin-orbit coupling is fully taken into account under a large crystal field. Despite delocalized Ir 5d states, the Jeff states form such narrow bands that even a small correlation energy leads to the Jeff=1/2 Mott ground state with unique electronic and magnetic behaviors, suggesting a new class of Jeff quantum spin driven correlated-electron phenomena.

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