| 1. |
- Aad, G, et al.
(författare)
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- 2015
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swepub:Mat__t
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| 2. |
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| 3. |
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| 4. |
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| 5. |
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| 6. |
- De Ferrari, G. M., et al.
(författare)
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Chronic vagus nerve stimulation: a new and promising therapeutic approach for chronic heart failure
- 2011
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Ingår i: European heart journal. - : Oxford University Press (OUP). - 1522-9645 .- 0195-668X. ; 32:7, s. 847-855
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Tidskriftsartikel (refereegranskat)abstract
- AIMS: In chronic heart failure (CHF), reduced vagal activity correlates with increased mortality and acute decompensation. Experimentally, chronic vagus nerve stimulation (VNS) improved left ventricular (LV) function and survival; clinically, it is used for the treatment of drug-refractory epilepsy. We assessed safety and tolerability of chronic VNS in symptomatic CHF patients, using a novel implantable nerve stimulation system. The secondary goal was to obtain preliminary data on clinical efficacy. METHODS AND RESULTS: This multi-centre, open-label phase II, two-staged study (8-patient feasibility phase plus 24-patient safety and tolerability phase) enrolled 32 New York Heart Association (NYHA) class II-IV patients [age 56 +/- 11 years, LV ejection fraction (LVEF) 23 +/- 8%]. Right cervical VNS with CardioFit (BioControl Medical) implantable system started 2-4 weeks after implant, slowly raising intensity; patients were followed 3 and 6 months thereafter with optional 1-year follow-up. Overall, 26 serious adverse events (SAEs) occurred in 13 of 32 patients (40.6%), including three deaths and two clearly device-related AEs (post-operative pulmonary oedema, need of surgical revision). Expected non-serious device-related AEs (cough, dysphonia, and stimulation-related pain) occurred early but were reduced and disappeared after stimulation intensity adjustment. There were significant improvements (P < 0.001) in NYHA class quality of life, 6-minute walk test (from 411 +/- 76 to 471 +/- 111 m), LVEF (from 22 +/- 7 to 29 +/- 8%), and LV systolic volumes (P = 0.02). These improvements were maintained at 1 year. CONCLUSIONS: This open-label study shows that chronic VNS in CHF patients with severe systolic dysfunction may be safe and tolerable and may improve quality of life and LV function. A controlled clinical trial appears warranted.
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| 7. |
- Hellwig, M. Ay. O, et al.
(författare)
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Oxidation of epitaxial Y(0001) films
- 2008
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Ingår i: Applied Surface Science. - : Elsevier BV. - 0169-4332 .- 1873-5584. ; 254:10, s. 3184-3190
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Tidskriftsartikel (refereegranskat)abstract
- We have investigated the oxidation behavior of MBE grown epitaxial Y(0 0 0 1)/Nb(1 1 0) films on sapphire (11 (2) over bar0) substrates at elevated temperatures under atmospheric conditions with a combination of experimental methods. At room temperature X-ray diffraction (XRD) reveals the formation of a 25 A thick YOxHx layer at the surface, while simultaneously oxide growth proceeds along defect lines normal to the film plane, resulting in the formation of a single crystalline cubic Y2O3 (2 2 2) phase. Furthermore, nuclear resonance analysis (NRA) reveals that hydrogen penetrates into the sample and transforms the entire Y film into the hydride YH2 phase. Additional annealing in air leads to further oxidation radially out from the already existing oxide channels. Finally material transport during oxidation results in the formation of conically shaped oxide precipitations at the surface above the oxide channels as observed by atomic force microscopy (AFM).
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| 8. |
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| 9. |
- Johnston, Jennifer J., et al.
(författare)
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Molecular Analysis Expands the Spectrum of Phenotypes Associated with GLI3 Mutations
- 2010
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Ingår i: Human Mutation. - : Hindawi Limited. - 1059-7794. ; 31:10, s. 1142-1154
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Tidskriftsartikel (refereegranskat)abstract
- A range of phenotypes including Greig cephalopolysyndactyly and Pallister-Hall syndromes (GCPS, PHS) are caused by pathogenic mutation of the GLI3 gene. To characterize the clinical variability of GLI3 mutations, we present a subset of a cohort of 174 probands referred for GLI3 analysis. Eighty-one probands with typical GCPS or PHS were previously reported, and we report the remaining 93 probands here. This includes 19 probands (12 mutations) who fulfilled clinical criteria for GCPS or PHS, 48 probands (16 mutations) with features of GCPS or PHS but who did not meet the clinical criteria (sub-GCPS and sub-PHS), 21 probands (6 mutations) with features of PHS or GCPS and oral-facial- digital syndrome, and 5 probands (1 mutation) with nonsyndromic polydactyly. These data support previously identified genotype-phenotype correlations and demonstrate a more variable degree of severity than previously recognized. The finding of GLI3 mutations in patients with features of oral-facial-digital syndrome supports the observation that GLI3 interacts with cilia. We conclude that the phenotypic spectrum of GLI3 mutations is broader than that encompassed by the clinical diagnostic criteria, but the genotype-phenotype correlation persists. Individuals with features of either GCPS or PHS should be screened for mutations in GLI3 even if they do not fulfill clinical criteria. Hum Mutat 31:1142-1154, 2010. (C) 2010 Wiley-Liss, Inc.
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| 10. |
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| 11. |
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| 12. |
- Asadollahi, Ali, et al.
(författare)
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Fabrication of relaxed germanium on insulator via room temperature wafer bonding
- 2014
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Ingår i: ECS Transactions. - : Electrochemical Society. - 1938-6737. ; , s. 533-541
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Konferensbidrag (refereegranskat)abstract
- We report on the fabrication of, high quality, monocrystalline relaxed Germanium with ultra-low roughness on insulator (GeOI) using low-temperature direct wafer bonding. We observe that a two-step epitaxially grown germanium film fabricated on silicon by reduced pressure chemical vapor deposition can be directly bonded to a SiO2 layer using a thin Al2O3 as bonding mediator. After removing the donor substrate silicon the germanium layer exhibits a complete relaxation without degradation in crystalline quality and no stress in the film. . The results suggest that the fabricated high quality GeOI substrate is a suitable platform for high performance device applications.
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| 13. |
- Bruessing, F., et al.
(författare)
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Magnetization and magnetization reversal in epitaxial Fe/Cr/Co asymmetric spin-valve systems
- 2012
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Ingår i: Physical Review B. Condensed Matter and Materials Physics. - 1098-0121 .- 1550-235X. ; 85:17, s. 174409-
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Tidskriftsartikel (refereegranskat)abstract
- We have investigated asymmetric Fe/Cr/Co/Cr superlattices with two magnetic layers of Fe and Co, which are different with respect to their magnetic properties: magnetization, coercivity, and magnetic anisotropy. The magnetic layers are weakly coupled via a mediating Cr spacer layer providing an antiferromagnetic alignment of adjacent layers. The magnetic structure of these spin-valve-like Fe/Cr/Co/Cr superlattices was analyzed from the remanent state up to saturation via polarized neutron scattering and polarized neutron reflectivity (PNR). Furthermore, the domain structure in remanence was imaged via polarized x-ray photoemission electron microscopy (XPEEM). This analysis reveals that the Co magnetization strongly affects the Fe domain structure, while the layer magnetization is collinear from the remanent antiparallel state up to the ferromagnetic saturation state. However, for certain Co layer thicknesses, the as-grown remanent state exhibits a noncollinear antiferromagnetic spin structure, which cannot be recovered after applying a magnetic field. However, the noncollinear structure is reproducible with freshly grown superlattices.
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| 14. |
- Devishvili, A., et al.
(författare)
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SuperADAM : Upgraded polarized neutron reflectometer at the Institut Laue-Langevin
- 2013
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Ingår i: Review of Scientific Instruments. - : AIP Publishing. - 0034-6748 .- 1089-7623. ; 84:2, s. 025112-
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Tidskriftsartikel (refereegranskat)abstract
- A new neutron reflectometer SuperADAM has recently been built and commissioned at the Institut Laue-Langevin, Grenoble, France. It replaces the previous neutron reflectometer ADAM. The new instrument uses a solid state polarizer/wavelength filter providing a highly polarized (up to 98.6%) monochromatic neutron flux of 8 x 10(4) n cm(-2) s(-1) with monochromatization Delta lambda/lambda = 0.7% and angular divergence Delta alpha = 0.2 mrad. The instrument includes both single and position sensitive detectors. The position sensitive detector allows simultaneous measurement of specular reflection and off-specular scattering. Polarization analysis for both specular reflection and off-specular scattering is achieved using either mirror analyzers or a He-3 spin filter cell. High efficiency detectors, low background, and high flux provides a dynamic range of up to seven decades in reflectivity. Detailed specifications and the instrument capabilities are illustrated with examples of recently collected data in the fields of thin film magnetism and thin polymer films.
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| 15. |
- Ferguson, J.W., et al.
(författare)
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Combining turbine blade-strike and life cycle models to assess mitigation strategies for fish passing dams
- 2008
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Ingår i: Canadian Journal of Fisheries and Aquatic Sciences. - 0706-652X .- 1205-7533. ; 65:8, s. 1568-1585
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Tidskriftsartikel (refereegranskat)abstract
- The combined model produced a tool for evaluating effects on fish populations from passage through hydro-power turbines at dams. Mean blade-strike mortality was higher for adult Atlantic salmon (Salmo salar) and sea-run brown trout (Salmo trutta) (25.2%-45.3%) than for juveniles (5.3%-9.7%). Based on life cycle modeling, salmon populations in two Swedish rivers responded differently to strategies for mitigating mortality caused by fish striking turbine blades. Although population growth rates increased up to 3% and were relatively similar for both rivers. the relative increase in the number of female salmon escaping above a dam annually after 20 years when both juveniles and adults were protected was greater in the River Pitealven (68%) than in the River Vindelalven (46%) and was approximately four times greater in the River Pitealven (38% vs. 10%) when only adults were protected. These population responses were not predicted by estimates of mortality through turbines. They showed the model could be used to evaluate strategies to conserve fish populations affected by dams located in fish migratory corridors and how postspawn adults contributed to population productivity.
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| 16. |
- Fraerman, A. A., et al.
(författare)
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Magnetic force microscopy of helical states in multilayer nanomagnets
- 2008
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Ingår i: Journal of Applied Physics. - : AIP Publishing. - 0021-8979 .- 1089-7550. ; 103:7, s. 073916-
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Tidskriftsartikel (refereegranskat)abstract
- We have used magnetic force microscopy (MFM) to investigate noncollinear helical states in multilayer nanomagnets, consisting of a stack of single domain ferromagnetic disks separated by insulating nonmagnetic spacers. The nanomagnets were fabricated from a [Co/Si]x3 multilayer thin film structure by electron beam lithography and ion beam etching. The structural parameters (Co layer and spacer thicknesses) were optimized to obtain a clear spiral signature in the MFM contrast, taking into account the magnetostatic interaction between the layers. MFM contrast corresponding to the helical states with different helicities was observed for the optimized structure with Co layer thicknesses of 16, 11, and 8 nm, and with 3 nm Si spacer thickness.
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| 17. |
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| 18. |
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| 19. |
- Kravtsov, E, et al.
(författare)
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Fine-tuning of the spin-density-wave state in Cr/V heterostructures via hydrogen uptake
- 2009
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Ingår i: Journal of Physics. - : IOP Publishing. - 0953-8984 .- 1361-648X. ; 21:33, s. 336004-
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Tidskriftsartikel (refereegranskat)abstract
- We show that the magnetic state in rather thick Cr films can be finely tuned via hydrogen uptake into adjacent vanadium layers at rather low hydrogen pressures. By changing the hydrogen concentration and, hence, the electronic structure in the V layers, it is possible to affect the global properties of spin-density waves (SDWs) in Cr layers, including the SDW period and the Neel temperature. We provide direct experimental evidence that hydrogen uptake into V layers can be used to switch between incommensurate and commensurate SDW states in a reproducible way.
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| 20. |
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| 21. |
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| 22. |
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| 23. |
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| 24. |
- Leiner, V, et al.
(författare)
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Deuterium in 001-oriented Mo0.5V0.5/V : Density profile on the atomic level
- 2002
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Ingår i: Physical Review B. Condensed Matter and Materials Physics. - 1098-0121 .- 1550-235X. ; 66:23
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Tidskriftsartikel (refereegranskat)abstract
- We have investigated the deuterium density profile in a Mo0.5V0.5/V superlattice along the direction parallel to the surface normal, using neutron reflectivity. To increase the sensitivity to changes in the deuterium density profile, in particular at the interfaces, we have carefully selected the thickness ratio of the constituents. Furthermore, the alloy composition of the Mo0.5V0.5 layer was chosen so that no depletion zone of hydrogen (deuterium) is expected at the interface in the low concentration limit. The neutron reflectivity results yield, however, a clear evidence of a depletion zone at the interfaces, with an extension of at least one monolayer. The appearance of a depletion layer is inferred to originate from the H-H interaction. Finally, by simultaneously monitoring the expansion and the concentration, we determined the elastic response of the V layers, and we prove the presence of nonlinear elastic response associated to a change of site occupancy.
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| 25. |
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| 26. |
- Nemec, K, et al.
(författare)
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Functional modulation of PTH1R activation and signaling by RAMP2
- 2022
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Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 1091-6490. ; 119:32, s. e2122037119-
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Tidskriftsartikel (refereegranskat)abstract
- Receptor-activity-modifying proteins (RAMPs) are ubiquitously expressed membrane proteins that associate with different G protein–coupled receptors (GPCRs), including the parathyroid hormone 1 receptor (PTH1R), a class B GPCR and an important modulator of mineral ion homeostasis and bone metabolism. However, it is unknown whether and how RAMP proteins may affect PTH1R function. Using different optical biosensors to measure the activation of PTH1R and its downstream signaling, we describe here that RAMP2 acts as a specific allosteric modulator of PTH1R, shifting PTH1R to a unique preactivated state that permits faster activation in a ligand-specific manner. Moreover, RAMP2 modulates PTH1R downstream signaling in an agonist-dependent manner, most notably increasing the PTH-mediated Gi3 signaling sensitivity. Additionally, RAMP2 increases both PTH- and PTHrP-triggered β-arrestin2 recruitment to PTH1R. Employing homology modeling, we describe the putative structural molecular basis underlying our functional findings. These data uncover a critical role of RAMPs in the activation and signaling of a GPCR that may provide a new venue for highly specific modulation of GPCR function and advanced drug design.
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| 27. |
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| 28. |
- N'Guessan, PD., et al.
(författare)
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The UspA1 protein of Moraxella catarrhalis induces CEACAM-1-dependent apoptosis in alveolar epithelial cells.
- 2007
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Ingår i: Journal of Infectious Diseases. - : Oxford University Press (OUP). - 1537-6613 .- 0022-1899. ; 195:11, s. 1651-1660
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Tidskriftsartikel (refereegranskat)abstract
- Moraxella catarrhalis is a major cause of exacerbations of chronic obstructive pulmonary disease (COPD) and emphysema. M. catarrhalis–specific UspA1 and the epithelial carcinoembryonic antigen-related cell adhesion molecule (CEACAM1) were required to induce apoptosis. M. catarrhalis–induced apoptosis was significantly enhanced in HeLa cells stably transfected with CEACAM1, compared with HeLa cells not expressing CEACAM1. Infected cells showed increased activity of caspases 3, 6, and 9 but not of caspase 8. Reduced expression of Bcl-2, translocation of Bax into the mitochondria, and cytosolic increase of apoptosis-inducing factor in M. catarrhalis–infected cells implicated the involvement of mitochondrial death pathways. In conclusion, M. catarrhalis induced apoptosis in pulmonary epithelial cells—a process that was triggered by interaction between CEACAM1 and UspA1. Thus, M. catarrhalis–induced apoptosis of pulmonary epithelial cells may contribute to the development of COPD and emphysema.
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| 29. |
- Nowak, G., et al.
(författare)
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Superconducting spin valves based on epitaxial Fe/V superlattices
- 2008
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Ingår i: Physical review B. Condensed matter and materials physics. - 1550-235X. ; 78:13, s. 134520-
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Tidskriftsartikel (refereegranskat)abstract
- In superconducting spin valves of the type S/F1/N/F2 or F1/S/F2 with a superconducting layer S, two ferromagnetic layers F1 and F2, and a normal metallic layer N, the superconducting transition temperature T-S depends on the relative magnetization direction of the ferromagnetic layers F1 and F2. The difference of the transition temperature Delta T-S=T-s(AP)-T-s(P) with the magnetization direction of F1 and F2 either antiparallel or parallel is called the superconducting spin valve effect. We have prepared both types of spin valves by growing Fe/V thin-film heterostructures with epitaxial quality on MgO(001) substrates. In the S/F1/N/F2-type spin valves the ferromagnetic layers were the first two Fe layers of a [Fe/V] superlattice coupled antiferromagnetically via the interlayer exchange interaction. Here we observed a superconducting spin valve shift of up to Delta T-S approximate to 200 mK when aligning the sublattice magnetization in an external magnetic field. In the F1/S/F2-type spin valves the ferromagnetic layer F1 was either a [Fe/V] or a [FexV1-x/V] superlattice, the F2 layer was a Fe-, a Co-, or a FexV1-x film. Using weakly ferromagnetic FexV1-x alloy layers as F1 and F2 we find a spin valve effect of up to Delta T-S approximate to 20 mK, which is more than a factor of 2 larger than reported in the literature before for spin valves with comparable transition temperatures. Our results indicate that a high interface transparency and a large superconducting correlation length are prerequisites for the observation of a sizable superconducting spin valve effect.
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| 30. |
- Remhof, A., et al.
(författare)
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Remote control of the Fe magnetic moment in magnetic heterostructures
- 2007
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Ingår i: Europhysics letters. - : IOP Publishing. - 0295-5075 .- 1286-4854. ; 79:3, s. 37003-
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Tidskriftsartikel (refereegranskat)abstract
- In magnetic superlattices with interlayer exchange coupling, not only the coupling strength but also the magnetic moment of the ferromagnetic layer can be altered non-locally by modifying the electronic structure of the non-magnetic spacer layer. Specifically, changes of the electronic structure of the V spacer layers in Fe/V (001) superlattices are seen to affect the adjacent Fe layers. By reversibly loading the V layer with hydrogen, the magnetic moment of Fe increases, whereas the induced magnetic moment in V remains unchanged. The nature of this remote and non-local control of the magnetic moment is connected with a d-electron charge transfer and effective shift of the Fermi level relative to the d-bands of Fe and V, as elucidated on the basis of self-consistent electronic structure calculations.
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| 31. |
- Remhof, A., et al.
(författare)
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Stability of the induced magnetic V moment in Fe/V superlattices upon hydrogen loading
- 2007
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Ingår i: Superlattices and Microstructures. - : Elsevier BV. - 0749-6036 .- 1096-3677. ; 41:2-3, s. 127-131
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Tidskriftsartikel (refereegranskat)abstract
- We report on the stability of the V magnetic moment within Fe/V superlattices upon H-uptake. At the Fe/V interface V atoms acquire a magnetic moment, antiparallel aligned to the Fe moments. Upon hydrogen loading the saturation magnetization was found to increase. We utilized element specific X-ray resonant magnetic scattering to address the response of the induced V moments. An epitaxial [Fe(5ML)/V (16ML)]×30 superlattice was employed. The soft x-ray measurements were carried out using the ALICE diffractometer at BESSY II in Berlin, Germany. The data clearly show the stability of the V moment upon H-loading. No change of the magnetic asymmetry at the V edge could be recognized. Our measurements confirm ab-initio calculations predicting a stable V moment and an increase of the Fe moment in H loaded Fe/V superlattices.
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| 32. |
- Sawakuchi, A. O., et al.
(författare)
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Luminescence of quartz and feldspar fingerprints provenance and correlates with the source area denudation in the Amazon River basin
- 2018
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Ingår i: Earth and Planetary Science Letters. - : Elsevier. - 0012-821X .- 1385-013X. ; 492, s. 152-162
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Tidskriftsartikel (refereegranskat)abstract
- The Amazon region hosts the world's largest watershed spanning from high elevation Andean terrains to lowland cratonic shield areas in tropical South America. This study explores variations in optically stimulated luminescence (OSL) and infrared stimulated luminescence (IRSL) signals in suspended silt and riverbed sands retrieved from major Amazon rivers. These rivers drain Pre-Cambrian to Cenozoic source rocks in areas with contrasting denudation rates. In contrast to the previous studies, we do not observe an increase in the OSL sensitivity of quartz with transport distance; for example, Tapajos and Xingu Rivers show more sensitive quartz than Solimbes and Madeira Rivers, even though the latter have a significantly larger catchment area and longer sediment transport distance. Interestingly, high sensitivity quartz is observed in rivers draining relatively stable Central Brazil and Guiana shield areas (denudation rate xi = 0.04 mm yr(-1)), while low sensitivity quartz occurs in less stable Andean terrains (xi = 0.24 mm yr(-1)). An apparent linear correlation between quartz OSL sensitivity and denudation rate suggests that OSL sensitivity may be used as a proxy for erosion rates in the Amazon basin. Furthermore, luminescence sensitivity measured in sand or silt arises from the same mineral components (quartz and feldspar) and clearly discriminates between Andean and shield sediments, avoiding the grain size bias in provenance analysis. These results have implications for using luminescence sensitivity as a proxy for Andean and shield contributions in the stratigraphic record, providing a new tool to reconstruct past drainage configurations within the Amazon basin.
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| 33. |
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| 34. |
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| 35. |
- Stillesjo, F, et al.
(författare)
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Hydrogen-induced lattice expansion in a (001)-oriented Mo/V superlattice
- 1996
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Ingår i: PHYSICAL REVIEW B-CONDENSED MATTER. - : AMER INST PHYSICS. - 0163-1829. ; 54:5, s. 3079-3083
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- The hydrogen-induced lattice expansion in a Mo/V single-crystal superlattice (L(V)/L(Mo)=2 nm/2 nm) has been studied by x-ray diffraction in the temperature range 20-500 degrees C and hydrogen pressures ranging from 5-625 torr in a vacuum x-ray furnace. F
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| 36. |
- Uzdin, M, et al.
(författare)
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Transition from spin-density-wave to layered antiferromagnetic state induced by hydrogen as a test for the origin of spin-density waves in chromium
- 2009
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Ingår i: Physical Review B. Condensed Matter and Materials Physics. - 1098-0121 .- 1550-235X. ; 80:17, s. 174418-
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Tidskriftsartikel (refereegranskat)abstract
- Neutron scattering experiments of Cr/V(001) superlattices are discussed, which show that the incommensurate spin-density-wave (SDW) in thick Cr layers becomes suppressed when the V spacer layers are loaded with hydrogen. The hydrogen loading triggers a transition from the incommensurate SDW state to a commensurate antiferromagnetic state. Model Hamiltonian calculations are presented, which show that this transition is not connected with the nesting property of the Cr Fermi surface. Instead, the transition is a manifestation of the antiferromagnetic ground state of Cr, which is separated from the incommensurate SDW state by an energy barrier. Hydrogen is identified as an effective trigger for reducing the activation barrier, enabling the system to relax to the ground state.
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| 37. |
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| 38. |
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| 39. |
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| 40. |
- Van Kampen, M., et al.
(författare)
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On the realization of artificial XY spin chains
- 2005
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Ingår i: Journal of Physics. - 0953-8984 .- 1361-648X. ; 17:2, s. L27-L33
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Tidskriftsartikel (refereegranskat)abstract
- Spin chains are the most elementary entities in the study of magnetic ordering behavior. The authors describe a route toward the realization of artificial XY spin chains. Using thin-film deposition and e-beam lithog., 300 and 550 nm diam. pillars consisting of alternating disks of permalloy and Al2O3 were made. Shape anisotropy forces the magnetization in plane, creating a chain of two-dimensional magnetic moments →i. The disks couple to each other by their dipolar stray fields, resulting in an interaction Jij→i·→j, with Jij the coupling between disks i and j. This form closely resembles a chain of xy spins, coupled by effective interactions Jij. The authors present a magnetic characterization of the pillars, and compare the results with model calcns. Also, spin dynamics and ordering phenomena are addressed.
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| 41. |
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| 42. |
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| 43. |
- Yanson, I. K., et al.
(författare)
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Spin Torques in Point Contacts to Exchange-Biased Ferromagnetic Films
- 2010
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Ingår i: IEEE transactions on magnetics. - 0018-9464 .- 1941-0069. ; 46:6, s. 2094-2096
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Tidskriftsartikel (refereegranskat)abstract
- Hysteretic magneto-resistance of point contacts formed between non-magnetic tips and single ferromagnetic films exchange-pinned by antiferromagnetic films is investigated. The analysis of the measured current driven and field driven hysteresis agrees with the recently proposed model of the surface spin-valve, where the spin orientation at the interface can be different from that in the bulk of the film. The switching in magneto-resistance at low fields is observed to depend significantly on the direction of the exchange pinning, which allows identifying this transition as a reversal of interior spins of the pinned ferromagnetic films. The switching at higher fields is thus due to a spin reversal in the point contact core, at the top surface of the ferromagnet, and does not exhibit any clear field offset when the exchange-pinning direction or the magnetic field direction is varied. This magnitude of the switching field of the surface spins varies substantially from contact to contact and sometimes from sweep to sweep, which suggests that the surface coercivity can change under very high current densities and/or due to the particular microstructure of the point contact. In contrast, no changes in the effect of the exchange biasing on the interior spins are observed at high currents, possibly due to the rapid drop in the current density away from nanometer sized point contact cores.
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| 44. |
- Zabel, B A, et al.
(författare)
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Human G protein-coupled receptor GPR-9-6/CC chemokine receptor 9 is selectively expressed on intestinal homing T lymphocytes, mucosal lymphocytes, and thymocytes and is required for thymus-expressed chemokine-mediated chemotaxis
- 1999
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Ingår i: Journal of Experimental Medicine. - 1540-9538. ; 190:9, s. 1241-1256
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Tidskriftsartikel (refereegranskat)abstract
- TECK (thymus-expressed chemokine), a recently described CC chemokine expressed in thymus and small intestine, was found to mediate chemotaxis of human G protein-coupled receptor GPR-9-6/L1.2 transfectants. This activity was blocked by anti-GPR-9-6 monoclonal antibody (mAb) 3C3. GPR-9-6 is expressed on a subset of memory alpha4beta7(high) intestinal trafficking CD4 and CD8 lymphocytes. In addition, all intestinal lamina propria and intraepithelial lymphocytes express GPR-9-6. In contrast, GPR-9-6 is not displayed on cutaneous lymphocyte antigen-positive (CLA(+)) memory CD4 and CD8 lymphocytes, which traffic to skin inflammatory sites, or on other systemic alpha4beta7(-)CLA(-) memory CD4/CD8 lymphocytes. The majority of thymocytes also express GPR-9-6, but natural killer cells, monocytes, eosinophils, basophils, and neutrophils are GPR-9-6 negative. Transcripts of GPR-9-6 and TECK are present in both small intestine and thymus. Importantly, the expression profile of GPR-9-6 correlates with migration to TECK of blood T lymphocytes and thymocytes. As migration of these cells is blocked by anti-GPR-9-6 mAb 3C3, we conclude that GPR-9-6 is the principal chemokine receptor for TECK. In agreement with the nomenclature rules for chemokine receptors, we propose the designation CCR-9 for GPR-9-6. The selective expression of TECK and GPR-9-6 in thymus and small intestine implies a dual role for GPR-9-6/CCR-9, both in T cell development and the mucosal immune response.
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| 45. |
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| 46. |
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