| 1. |
- Delheusy, M., et al.
(författare)
-
X-ray investigation of subsurface interstitial oxygen at Nb/oxide interfaces
- 2008
-
Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 92:10
-
Tidskriftsartikel (refereegranskat)abstract
- We have investigated the dissolution of a natural oxide layer on a Nb(110) surface upon heating, combining x-ray reflectivity, grazing incidence diffuse scattering, and core-level spectroscopy. The natural oxide reduces after heating to 145 degrees C partially from Nb2O5 to NbO2, and an enrichment in subsurface interstitial oxygen by similar to 70% in a depth of 100 A is observed. After heating to 300 degrees C, the oxide reduces to NbO and the surplus subsurface oxygen gets dissolved into the bulk. Our approach can be applied for further investigation of the effect of subsurface interstitial oxygen on the performance of niobium rf cavities. (C) 2008 American Institute of Physics. (C) 2008 American Institute of Physics.
|
|
| 2. |
- Gustafson, Johan, et al.
(författare)
-
Structure of a thin oxide film on Rh(100)
- 2005
-
Ingår i: Physical Review B (Condensed Matter and Materials Physics). - 1098-0121. ; 71:11
-
Tidskriftsartikel (refereegranskat)abstract
- The initial oxidation of Rh(100) has been studied using high resolution core level spectroscopy, low energy electron diffraction, surface x-ray diffraction, scanning tunneling microscopy, and density functional theory. We report a structural study of an oxygen induced structure displaying a c(8x2) periodicity at an oxygen pressure above 10(-5) mbar and using a sample temperature of 700 K. Our experimental and theoretical data demonstrate that this structure is due to the formation of a thin surface oxide with a hexagonal trilayer O-Rh-O structure.
|
|
| 3. |
- Knip, Mikael, et al.
(författare)
-
Effect of Hydrolyzed Infant Formula vs Conventional Formula on Risk of Type 1 Diabetes The TRIGR Randomized Clinical Trial
- 2018
-
Ingår i: Journal of the American Medical Association (JAMA). - : AMER MEDICAL ASSOC. - 0098-7484 .- 1538-3598. ; 319:1, s. 38-48
-
Tidskriftsartikel (refereegranskat)abstract
- IMPORTANCE Early exposure to complex dietary proteins may increase the risk of type 1 diabetes in children with genetic disease susceptibility. There are no intact proteins in extensively hydrolyzed formulas. OBJECTIVE To test the hypothesis that weaning to an extensively hydrolyzed formula decreases the cumulative incidence of type 1 diabetes in young children. DESIGN, SETTING, AND PARTICIPANTS An international double-blind randomized clinical trial of 2159 infants with human leukocyte antigen-conferred disease susceptibility and a first-degree relative with type 1 diabetes recruited from May 2002 to January 2007 in 78 study centers in 15 countries; 1081 were randomized to be weaned to the extensively hydrolyzed casein formula and 1078 to a conventional formula. The follow-up of the participants ended on February 28, 2017. INTERVENTIONS The participants received either a casein hydrolysate or a conventional adapted cows milk formula supplemented with 20% of the casein hydrolysate. The minimum duration of study formula exposure was 60 days by 6 to 8 months of age. MAIN OUTCOMES AND MEASURES Primary outcome was type 1 diabetes diagnosed according to World Health Organization criteria. Secondary outcomes included age at diabetes diagnosis and safety (adverse events). RESULTS Among 2159 newborn infants (1021 female [47.3%]) who were randomized, 1744 (80.8%) completed the trial. The participants were observed for a median of 11.5 years (quartile [Q] 1-Q3, 10.2-12.8). The absolute risk of type 1 diabetes was 8.4% among those randomized to the casein hydrolysate (n = 91) vs 7.6% among those randomized to the conventional formula (n = 82) (difference, 0.8%[95% CI, -1.6% to 3.2%]). The hazard ratio for type 1 diabetes adjusted for human leukocyte antigen risk group, duration of breastfeeding, duration of study formula consumption, sex, and region while treating study center as a random effect was 1.1 (95% CI, 0.8 to 1.5; P = .46). The median age at diagnosis of type 1 diabetes was similar in the 2 groups (6.0 years [Q1-Q3, 3.1-8.9] vs 5.8 years [Q1-Q3, 2.6-9.1]; difference, 0.2 years [95% CI, -0.9 to 1.2]). Upper respiratory infections were the most common adverse event reported (frequency, 0.48 events/year in the hydrolysate group and 0.50 events/year in the control group). CONCLUSIONS AND RELEVANCE Among infants at risk for type 1 diabetes, weaning to a hydrolyzed formula compared with a conventional formula did not reduce the cumulative incidence of type 1 diabetes after median follow-up for 11.5 years. These findings do not support a need to revise the dietary recommendations for infants at risk for type 1 diabetes.
|
|
| 4. |
- Lundgren, Edvin, et al.
(författare)
-
Kinetic hindrance during the initial oxidation of Pd(100) at ambient pressures
- 2004
-
Ingår i: Physical Review Letters. - 1079-7114. ; 92:4
-
Tidskriftsartikel (refereegranskat)abstract
- The oxidation of the Pd(100) surface at oxygen pressures in the 10(-6) to 10(3) mbar range and temperatures up to 1000 K has been studied in situ by surface x-ray diffraction (SXRD). The results provide direct structural information on the phases present in the surface region and on the kinetics of the oxide formation. Depending on the (T,p) environmental conditions, we observe either a thin (root5 x root5)R27degrees surface oxide or the growth of a rough, poorly ordered bulk oxide film of PdO predominantly with (001) orientation. By either comparison to the surface phase diagram from first-principles atomistic thermodynamics or by explicit time-resolved measurements we identify a strong kinetic hindrance to the bulk oxide formation even at temperatures as high as 675 K.
|
|
| 5. |
- Mattsson, Titti, et al.
(författare)
-
Country Reports
- 2020
-
Ingår i: Journal of Law, Medicine & Ethics. - : Cambridge University Press (CUP). - 1073-1105 .- 1748-720X. ; 47:4, s. 670-674
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- The country reports deal with the regulation of international direct-to-participant genomic research.
|
|
| 6. |
- Schmid, M, et al.
(författare)
-
Structure of Ag(111)-p(4x4)-O: No silver oxide
- 2006
-
Ingår i: Physical Review Letters. - 1079-7114. ; 96:14
-
Tidskriftsartikel (refereegranskat)abstract
- The structure of the oxygen-induced p(4x4) reconstruction of Ag(111) is determined by a combination of scanning tunneling microscopy, surface x-ray diffraction, core level spectroscopy, and density functional theory. We demonstrate that all previous models of this surface structure are incorrect and propose a new model which is able to explain all our experimental findings but has no resemblance to bulk silver oxide. We also shed some light on the limitations of current density functional theories and the potential role of van der Waals interactions in the stabilization of oxygen-induced surface reconstructions of noble metals.
|
|
| 7. |
- Stierle, A., et al.
(författare)
-
Real time observation of ultrathin epitaxial oxide growth during alloy oxidation
- 2007
-
Ingår i: New Journal of Physics. - : IOP Publishing. - 1367-2630. ; 9, s. 331-331
-
Tidskriftsartikel (refereegranskat)abstract
- We have studied the thermal oxidation of the intermetallic alloy CoGa in situ, in real time on the atomic scale, during the growth of an ultrathin, epitaxial Ga oxide layer. On the basis of an extended set of surface x-ray diffraction data, density functional theory calculations and core level spectroscopy data, we find that the oxide film consists of an oxygen ion double layer, which contains the basic building block of bulk beta- Ga2O3. The oxide formation takes place via the nucleation of two- dimensional, anisotropic oxide islands which laterally grow and coalesce. A dramatic increase of the oxide island size is observed for low O-2 pressures in the 10(-8) mbar regime, which we interpret as the onset of a step flow like growth mode. This allows us to conclude that thermal oxidation can be considered as a hetero- epitaxial growth process, that follows similar atomistic growth principles to molecular beam epitaxy. As a consequence, the structural perfection of the oxide layer can be tailored by the appropriate choice of oxygen pressure and temperature.
|
|
| 8. |
- Stierle, A, et al.
(författare)
-
Surface core level shift observed on NiAl(110)
- 2003
-
Ingår i: Surface Science. - 0039-6028. ; 529:3, s. 263-268
-
Tidskriftsartikel (refereegranskat)abstract
- Using high resolution core level spectroscopy, a surface core level shift towards lower binding energy of -0.13 eV is determined for the 2p level of the outwardly relaxed Al surface atoms on NiAl(110). Density functional theory based calculations with inclusion of final state effects yield a value of -0.14 eV for this shift in excellent agreement with experiment. We show that the initial state approximation yields a value of +0.09 eV, i.e. the inclusion of final state relaxation effects is vital not only to obtain the correct value but even the correct sign for this shift. (C) 2003 Elsevier Science B.V. All rights reserved.
|
|
| 9. |
- Stierle, A, et al.
(författare)
-
Surface x-ray study of the structure and morphology of the oxidized Pd(001) surface
- 2005
-
Ingår i: Journal of Chemical Physics. - : AIP Publishing. - 0021-9606 .- 1089-7690. ; 122:4
-
Tidskriftsartikel (refereegranskat)abstract
- The oxidation of Pd(100) and the formation of PdO was studied in situ using surface x-ray diffraction. A bulklike, epitaxial PdO film is formed at oxygen partial pressures beyond 1 mbar and sample temperatures exceeding 650 K. The main orientation is PdO(001)/Pd(001), based upon bulk reflections from the PdO film. By comparing with measurements from the Pd crystal truncation rods, we estimate an rms surface roughness of 6 Angstrom, in good agreement with previous high pressure scanning tunneling microscopy measurements. Finally, we observed the transformation from the (root5 x root5) surface oxide to PdO bulk oxide at 675 K and 50 mbar O-2 pressure.
|
|
