| 1. |
- Aad, G., et al.
(författare)
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- 2012
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swepub:Mat__t (refereegranskat)
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| 2. |
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| 3. |
- Gould, A., et al.
(författare)
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MOA-2010-BLG-523:" Failed Planet"= RS CVn Star
- 2013
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Ingår i: Astrophysical Journal. - 0004-637X. ; 763:2
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Tidskriftsartikel (refereegranskat)abstract
- The Galactic bulge source MOA-2010-BLG-523S exhibited short-term deviations from a standard microlensing light curve near the peak of an A(max) similar to 265 high-magnification microlensing event. The deviations originally seemed consistent with expectations for a planetary companion to the principal lens. We combine long-term photometric monitoring with a previously published high-resolution spectrum taken near peak to demonstrate that this is an RS CVn variable, so that planetary microlensing is not required to explain the light-curve deviations. This is the first spectroscopically confirmed RS CVn star discovered in the Galactic bulge.
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| 8. |
- Bensby, Thomas, et al.
(författare)
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Chemical evolution of the Galactic bulge as traced by microlensed dwarf and subgiant stars IV. Two bulge populations
- 2011
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Ingår i: Astronomy & Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 533
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Tidskriftsartikel (refereegranskat)abstract
- Based on high-resolution (R approximate to 42 000 to 48 000) and high signal-to-noise (S/N approximate to 50 to 150) spectra obtained with UVES/VLT, we present detailed elemental abundances (O, Na, Mg, Al, Si, Ca, Ti, Cr, Fe, Ni, Zn, Y, and Ba) and stellar ages for 12 new microlensed dwarf and subgiant stars in the Galactic bulge. Including previous microlensing events, the sample of homogeneously analysed bulge dwarfs has now grown to 26. The analysis is based on equivalent width measurements and standard 1-D LTE MARCS model stellar atmospheres. We also present NLTE Li abundances based on line synthesis of the Li-7 line at 670.8 nm. The results from the 26 microlensed dwarf and subgiant stars show that the bulge metallicity distribution (MDF) is double-peaked; one peak at [Fe/H] approximate to -0.6 and one at [Fe/H] approximate to +0.3, and with a dearth of stars around solar metallicity. This is in contrast to the MDF derived from red giants in Baade's window, which peaks at this exact value. A simple significance test shows that it is extremely unlikely to have such a gap in the microlensed dwarf star MDF if the dwarf stars are drawn from the giant star MDF. To resolve this issue we discuss several possibilities, but we can not settle on a conclusive solution for the observed differences. We further find that the metal-poor bulge dwarf stars are predominantly old with ages greater than 10 Gyr, while the metal-rich bulge dwarf stars show a wide range of ages. The metal-poor bulge sample is very similar to the Galactic thick disk in terms of average metallicity, elemental abundance trends, and stellar ages. Speculatively, the metal-rich bulge population might be the manifestation of the inner thin disk. If so, the two bulge populations could support the recent findings, based on kinematics, that there are no signatures of a classical bulge and that the Milky Way is a pure-disk galaxy. Also, recent claims of a flat IMF in the bulge based on the MDF of giant stars may have to be revised based on the MDF and abundance trends probed by our microlensed dwarf stars.
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| 10. |
- Holmfeldt, Linda, et al.
(författare)
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The genomic landscape of hypodiploid acute lymphoblastic leukemia
- 2013
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Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1546-1718 .- 1061-4036. ; 45:3, s. 242-252
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Tidskriftsartikel (refereegranskat)abstract
- The genetic basis of hypodiploid acute lymphoblastic leukemia (ALL), a subtype of ALL characterized by aneuploidy and poor outcome, is unknown. Genomic profiling of 124 hypodiploid ALL cases, including whole-genome and exome sequencing of 40 cases, identified two subtypes that differ in the severity of aneuploidy, transcriptional profiles and submicroscopic genetic alterations. Near-haploid ALL with 24-31 chromosomes harbor alterations targeting receptor tyrosine kinase signaling and Ras signaling (71%) and the lymphoid transcription factor gene IKZF3 (encoding AIOLOS; 13%). In contrast, low-hypodiploid ALL with 32-39 chromosomes are characterized by alterations in TP53 (91.2%) that are commonly present in nontumor cells, IKZF2 (encoding HELIOS; 53%) and RB1 (41%). Both near-haploid and low-hypodiploid leukemic cells show activation of Ras-signaling and phosphoinositide 3-kinase (PI3K)-signaling pathways and are sensitive to PI3K inhibitors, indicating that these drugs should be explored as a new therapeutic strategy for this aggressive form of leukemia.
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| 11. |
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| 12. |
- Hans, M., et al.
(författare)
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Effect of oxygen incorporation on the structure and elasticity of Ti-Al-O-N coatings synthesized by cathodic arc and high power pulsed magnetron sputtering
- 2014
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Ingår i: Journal of Applied Physics. - : AIP Publishing. - 0021-8979 .- 1089-7550. ; 116:9, s. 093515-
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Tidskriftsartikel (refereegranskat)abstract
- Ti-Al-O-N coatings were synthesized by cathodic arc and high power pulsed magnetron sputtering. The chemical composition of the coatings was determined by means of elastic recoil detection analysis and energy dispersive X-ray spectroscopy. The effect of oxygen incorporation on the stress-free lattice parameters and Young's moduli of Ti-Al-O-N coatings was investigated by X-ray diffraction and nanoindentation, respectively. As nitrogen is substituted by oxygen, implications for the charge balance may be expected. A reduction in equilibrium volume with increasing O concentration is identified by X-ray diffraction and density functional theory calculations of Ti-Al-O-N supercells reveal the concomitant formation of metal vacancies. Hence, the oxygen incorporation-induced formation of metal vacancies enables charge balancing. Furthermore, nanoindentation experiments reveal a decrease in elastic modulus with increasing O concentration. Based on ab initio data, two causes can be identified for this: First, the metal vacancy-induced reduction in elasticity; and second, the formation of, compared to the corresponding metal nitride bonds, relatively weak Ti-O and Al-O bonds.
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| 14. |
- Choi, S. G., et al.
(författare)
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Dielectric function spectra and critical-point energies of Cu2ZnSnSe4 from 0.5 to 9.0 eV
- 2012
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Ingår i: Journal of Applied Physics. - : AIP Publishing. - 0021-8979 .- 1089-7550. ; 111:3, s. 033506-
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Tidskriftsartikel (refereegranskat)abstract
- We present dielectric function epsilon=epsilon(1) + i epsilon(2) spectra and critical-point energies of Cu2ZnSnSe4 determined by spectroscopic ellipsometry from 0.5 to 9.0 eV. We reduce artifacts from surface overlayers to the maximum extent possible by performing chemical-mechanical polishing and wet-chemical etching of the surface of a Cu2ZnSnSe4 thin film. Ellipsometric data are analyzed by the multilayer model and the epsilon spectra are extracted. The data exhibit numerous spectral features associated with critical points, whose energies are obtained by fitting standard lineshapes to second energy derivatives of the data. The experimental results are in good agreement with the a spectra calculated within the GW quasi-particle approximation, and possible origins of the pronounced critical-point structures are identified.
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| 19. |
- Sarakinos, Kostas, et al.
(författare)
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On the phase formation of sputtered hafnium oxide and oxynitride films
- 2010
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Ingår i: Journal of Applied Physics. - : American Institute of Physics (AIP). - 0021-8979 .- 1089-7550. ; 108:1, s. 014904-
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Tidskriftsartikel (refereegranskat)abstract
- Hafnium oxynitride films are deposited from a Hf target employing direct current magnetron sputtering in an Ar-O(2)-N(2) atmosphere. It is shown that the presence of N(2) allows for the stabilization of the transition zone between the metallic and the compound sputtering mode enabling deposition of films at well defined conditions of target coverage by varying the O(2) partial pressure. Plasma analysis reveals that this experimental strategy facilitates control over the flux of the O(-) ions which are generated on the oxidized target surface and accelerated by the negative target potential toward the growing film. An arrangement that enables film growth without O(-) ion bombardment is also implemented. Moreover, stabilization of the transition sputtering zone and control of the O(-) ion flux without N(2) addition is achieved employing high power pulsed magnetron sputtering. Structural characterization of the deposited films unambiguously proves that the phase formation of hafnium oxide and hafnium oxynitride films with the crystal structure of HfO(2) is independent from the O(-) bombardment conditions. Experimental and theoretical data indicate that the presence of vacancies and/or the substitution of O by N atoms in the nonmetal sublattice favor the formation of the cubic and/or the tetragonal HfO(2) crystal structure at the expense of the monoclinic HfO(2) one.
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| 20. |
- Sharma, Manish, et al.
(författare)
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Older Patients with Myeloma Derive Similar Benefit from Autologous Transplantation
- 2014
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Ingår i: Biology of blood and marrow transplantation. - : Elsevier BV. - 1083-8791 .- 1523-6536. ; 20:11, s. 1796-1803
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Tidskriftsartikel (refereegranskat)abstract
- Autologous hematopoietic cell transplantation (AHCT) for plasma cell myeloma is performed less often in people >70 years old than in people <= 70 years old. We analyzed 11,430 AHCT recipients for plasma cell myeloma prospectively reported to the Center for International Blood and Marrow Transplant Research between 2008 and 2011, representing the majority of US AHCT activity during this period. Survival (OS) was compared in 3 cohorts: ages 18 to 59 years (n = 5818), 60 to 69 years (n = 4666), and >70 years (n = 946). Median OS was not reached for any cohort. In multivariate analysis, increasing age was associated with mortality (P = .0006). Myeloma-specific mortality was similar among cohorts at 12%, indicating an age-related effect on nonmyeloma mortality. Analyses were performed in a representative subgroup comparing relapse rate, progression-free survival (PFS), and nonrelapse mortality (NRM). One-year NRM was 0% for age >70 years and 2% for other ages (P = not significant). The three-year relapse rate was 56% in age 18 to 59 years, 61% in age 60 to 69 years, and 63% age >70 (P = not significant). Three-year PFS was similar at 42% in age 18 to 59 years, 38% in age 60 to 69 years, and 33% in age >70 years (P = not significant). Postrelapse survival was significantly worse for the older cohort (P = .03). Older subjects selected for AHCT derived similar antimyeloma benefit without worse NRM, relapse rate, or PFS.
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