| 1. |
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| 2. |
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| 3. |
- GUO, JH, et al.
(författare)
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RESONANT EXCITATION X-RAY-FLUORESCENCE FROM C-60
- 1995
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Ingår i: PHYSICAL REVIEW B-CONDENSED MATTER. - : AMER INST PHYSICS. ; 52:15
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- X-ray fluorescence of condensed C-60 has been recorded in high resolution using monochromatic synchrotron radiation excitation. Strong intensity modulation of constituent spectral features is observed with varying excitation energy up to 10 eV above thres
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| 4. |
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| 5. |
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| 6. |
- Duda, LC, et al.
(författare)
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Hydrogen-induced changes of the electronic states in ultrathin single-crystal vanadium layers
- 1997
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Ingår i: PHYSICAL REVIEW B-CONDENSED MATTER. - : AMER INST PHYSICS. - 0163-1829. ; 55:19, s. 12914-12917
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- The electronic structure of vanadium in an Fe/V (001) superlattice, exposed to a 100 torr hydrogen pressure, was investigated using soft-x-ray emission spectroscopy and first-principles band-structure calculations. We present x-ray emission spectra from t
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| 7. |
- Glans, P, et al.
(författare)
-
Selectively excited X-ray emission spectra of N-2
- 1996
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Ingår i: JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA. - : ELSEVIER SCIENCE BV. - 0368-2048. ; 82:3, s. 193-201
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Resonant and non-resonant X-ray emission spectra of N-2 are presented. The role of the parity selection rule in the case of homonuclear diatomic molecules is discussed thoroughly and illustrated by the X-ray emission spectra. We also discuss how the parit
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| 8. |
- Gunnelin, K, et al.
(författare)
-
Assigning x-ray absorption spectra by means of soft-x-ray emission spectroscopy
- 1998
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Ingår i: PHYSICAL REVIEW A. - : AMERICAN PHYSICAL SOC. - 1050-2947. ; 57:2, s. 864-872
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- The possibility to symmetry assign x-ray absorption spectra using x-ray emission spectroscopy is demonstrated. The oxygen K spectra of CO2 are used to illustrate the possibility to assign core excitations through excitation-energy and angular dependence o
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| 9. |
- Guo, J.H., et al.
(författare)
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Resonant excitation x-ray-fluorescence from C-60
- 1995
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Ingår i: Physical Review B Condensed Matter. - 0163-1829 .- 1095-3795. ; 52, s. 10681-
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Tidskriftsartikel (refereegranskat)abstract
- X-ray fluorescence of condensed C-60 has been recorded in high resolution using monochromatic synchrotron radiation excitation. Strong intensity modulation of constituent spectral features is observed with varying excitation energy up to 10 eV above threshold. The energy dependence is interpreted as due to resonant inelastic x-ray scattering, leading to symmetry selection rules governing the two-photon process in the fully symmetric molecule.
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| 10. |
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| 11. |
- MANCINI, DC, et al.
(författare)
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CHEMICAL-VAPOR-DEPOSITION OF CR, MO AND W THIN-FILMS INDUCED BY SYNCHROTRON-RADIATION
- 1995
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Ingår i: VACUUM. - : PERGAMON-ELSEVIER SCIENCE LTD. - 0042-207X. ; 46:8-10, s. 1165-1169
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- We demonstrate the ability to produce 1000 Angstrom thick metal containing films by using chemical vapour deposition (CVD) from Cr(CO)(6), Mo(CO)(6) and W(CO)(6) induced by synchrotron radiation (SR). The deposition is monitored in real time and in situ u
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| 12. |
- Nordgren, J, et al.
(författare)
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Resonant soft X-ray fluorescence spectra of molecules
- 1997
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Ingår i: APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING. - : SPRINGER VERLAG. - 0947-8396. ; 65:2, s. 97-105
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- A review is presented of some recent advancements in resonant soft X-ray fluorescence spectroscopy applied to molecules. The concept of inelastic scattering is discussed for molecules with an element of symmetry, which introduces degeneracy or near-degene
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| 13. |
- Skytt, P, et al.
(författare)
-
Lifetime-vibrational interference effects in the resonantly excited x-ray-emission spectra of CO
- 1997
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Ingår i: PHYSICAL REVIEW A. - : AMER INST PHYSICS. - 1050-2947. ; 55:1, s. 146-154
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- A systematic study of vibrational band profiles in resonantly excited x-ray-emission spectra of free molecules is made. Carbon and oxygen K-emission spectra of CO following core excitations, using narrow-bandpass synchrotron radiation, to the 2 pi orbital
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| 14. |
- Skytt, P, et al.
(författare)
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Probe depth variation in grazing exit soft-X-ray emission spectroscopy
- 1997
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Ingår i: NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT. - 0168-9002. ; 384:2-3, s. 558-562
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- The angular dependence of soft X-ray emission spectra from a sandwich structured sample has been studied. Greatly enhanced surface sensitivity is observed at grazing emission. Soft X-ray emission allows chemical state information to be obtained owing to h
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| 15. |
- Skytt, P, et al.
(författare)
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Quenching of symmetry breaking in resonant inelastic X-ray scattering by detuned excitation
- 1996
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Ingår i: PHYSICAL REVIEW LETTERS. - : AMER INST PHYSICS. - 0031-9007. ; 77:25, s. 5035-5038
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Observations made in oxygen K emission of CO2 show that the symmetry selective character of resonant x-ray emission is excitation energy dependent. Electronically dipole forbidden O K emission lines are observed for excitation at the O 1s --> pi* resonanc
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| 16. |
- Skytt, P, et al.
(författare)
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Role of screening and angular distributions in resonant x-ray emission of CO
- 1997
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Ingår i: PHYSICAL REVIEW A. - : AMER INST PHYSICS. - 1050-2947. ; 55:1, s. 134-145
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Resonantly excited carbon and oxygen x-ray-emission spectra of gaseous carbon monoxide are presented. Emission spectra obtained with selective excitation to the pi* valence orbital and to various Rydberg levels are compared to satellite-free nonresonant s
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| 17. |
- AGREN, H, et al.
(författare)
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SYMMETRY SELECTIVE RESONANT INELASTIC X-RAY-SCATTERING
- 1995
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Ingår i: PHYSICA B. - : ELSEVIER SCIENCE BV. - 0921-4526. ; 209:1-4, s. 105-107
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- We use two species with high point group symmetry, fullerene and benzene, to discuss important features of symmetry selective resonant inelastic X-ray scattering spectroscopy.
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| 18. |
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| 19. |
- Cesar, A, et al.
(författare)
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Resonant x-ray scattering beyond the Born-Oppenheimer approximation: Symmetry breaking in the oxygen resonant x-ray emission spectrum of carbon dioxide
- 1997
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Ingår i: Journal of Chemical Physics. - 0021-9606. ; 106:9, s. 3439-3456
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Tidskriftsartikel (refereegranskat)abstract
- Although resonant x-ray scattering of molecules fulfills strict electronic symmetry selection rules, as now firmly proven by. spectra of diatomic molecules, the accumulated body of data for polyatomic molecules indicates that an apparent breaking of these rules represents the common situation rather than the exception. The CO2 molecule provides a good example of symmetry breaking, with the. oxygen x-ray emission spectra showing strong intensity for transitions that are forbidden by the parity selection rule. We present time-independent and time-dependent theories for frequency-dependent resonant x-ray scattering beyond, the Born-Oppenheimer approximation in order to explore under what circumstances one can anticipate symmetry breaking in the spectra of polyatomic molecules. The theory starts out from the Kramers-Heisenberg dispersion relation and is generalized for vibrational degrees of freedom and for nonadiabatic coupling of the electronic (vibronic) states, including the frequency dependency of, the scattering cross section. Different Limiting cases and few-level models are considered. The symmetry breaking is proven to be the result of pseudo-Jahn-Teller-Like vibronic coupling between near-degenerate core-excited states. Thus vibromic interaction over the antisymmetric vibrational mode between the ''bright'' 1 sigma(g)(-1)2 pi(u)(-1) and ''dark'' 1 sigma(u)(-1)2 pi(u)(-1) intermediate states of CO2 allows transitions otherwise forbidden. The measurements and theory demonstrate that the symmetry-selective character of the resonant x-ray emission is strongly frequency dependent. The strong intensity of ''dipole-forbidden'' transitions in the pi* oxygen K spectrum at resonance is reduced monotonically with the detuning of the excitation energy from resonance, and the spectra become ''symmetry purified.'' Simulations with full vibronic coupling predict this feature of the x-ray scattering experiment and a few-level model explains the energy dependence of the symmetry selection and the symmetry purification at large detuning energies in the limit of narrowband photon excitation.
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| 20. |
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| 21. |
- FINKELSTEIN, LD, et al.
(författare)
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REDISTRIBUTION OF O2P-STATES IN LA2CUO4 BY SR-DOPING
- 1995
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Ingår i: SOLID STATE COMMUNICATIONS. - : PERGAMON-ELSEVIER SCIENCE LTD. - 0038-1098. ; 95:8, s. 503-506
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- The difference between the oxygen K-alpha X-ray emission spectra of in-plane oxygen in La2-xSrxCuO4 (x=0.07; 0.15), measured with selective fluorescence excitation, is compared with the difference of the corresponding oxygen 1s X-ray absorption spectra. I
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| 22. |
- Glans, Peter, et al.
(författare)
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Resonant x-ray emission spectroscopy of molecular oxygen
- 1996
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Ingår i: Physical Review Letters. - : AMER INST PHYSICS. - 0031-9007. ; 76:14, s. 2448-2451
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Tidskriftsartikel (refereegranskat)abstract
- Resonant soft x-ray emission spectroscopy has been applied to study the issue of symmetry breaking upon core-hole excitation in molecular oxygen. The results provide direct evidence that the inversion symmetry is not broken in the core-excited states. Furthermore, the experiments themselves demonstrate a new experimental technique of broad applicability for studies of electronic structure and excitation dynamics in free atoms and molecules.
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| 23. |
- Glans, Peter, et al.
(författare)
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Selectively excited x-ray emission spectra of N2
- 1996
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Ingår i: Journal of Electron Spectroscopy and Related Phenomena. - 0368-2048. ; 82:3, s. 193-201
-
Tidskriftsartikel (refereegranskat)abstract
- Resonant and non-resonant X-ray emission spectra of N-2 are presented. The role of the parity selection rule in the case of homonuclear diatomic molecules is discussed thoroughly and illustrated by the X-ray emission spectra. We also discuss how the parity selection rule and the angular anisotropy of the resonant X-ray emission may affect intensities in a fluorescence yield measurement of N-2. Simulated vibrational band profiles calculated using the lifetime-vibrational interference formula are found to be in excellent agreement with the experimental emission bands.
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| 24. |
- Gunnelin, K, et al.
(författare)
-
Assigning x-ray absorption spectra by means of soft-x-ray emission spectroscopy
- 1998
-
Ingår i: Physical Review A. Atomic, Molecular, and Optical Physics. - 1050-2947. ; 57:2, s. 864-872
-
Tidskriftsartikel (refereegranskat)abstract
- The possibility to symmetry assign x-ray absorption spectra using x-ray emission spectroscopy is demonstrated. The oxygen K spectra of CO2 are used to illustrate the possibility to assign core excitations through excitation-energy and angular dependence of resonantly excited x-ray emission spectra. The Rydberg-associated structures just below the ionization threshold in the O K x-ray absorption spectrum are assigned to be mainly due to excitations to orbitals of sigma(g) character. The results, which contradict some previous literature assignments, are supported by quantum-chemical calculations.
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| 25. |
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| 26. |
- Guo, JH, et al.
(författare)
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In situ and ex situ characterization of thin films by soft X-ray emission spectroscopy
- 2000
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Ingår i: JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA. - : ELSEVIER SCIENCE BV. - 0368-2048. ; 110:1-3, s. 41-67
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Tidskriftsartikel (refereegranskat)abstract
- Soft X-ray emission spectroscopy has been used as a chemical probe in the characterization of thin film materials. Some examples of soft X-ray emission studies are presented to show the chemical sensitivity, site selectivity and depth dependence of this m
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| 27. |
- GUO, JH, et al.
(författare)
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RESONANT AND NONRESONANT X-RAY-SCATTERING FROM C-70
- 1995
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Ingår i: CHEMICAL PHYSICS LETTERS. - : ELSEVIER SCIENCE BV. - 0009-2614. ; 235:1-2, s. 152-159
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Resonant and non-resonant X-ray scattering spectra of the C-70 molecule are presented and analyzed by ab initio Hartree-Fock calculations using a newly developed formalism for symmetry selective inelastic X-ray scattering. Compared to C-60, a weak excitat
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| 28. |
- Hjalgrim, Henrik, et al.
(författare)
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HLA-A alleles and infectious mononucleosis suggest a critical role for cytotoxic T-cell response in EBV-related Hodgkin lymphoma
- 2010
-
Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 107:14, s. 6400-6405
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Tidskriftsartikel (refereegranskat)abstract
- A proportion of classical Hodgkin lymphoma (HL) is believed to be causally related to infection with the ubiquitous lymphotropic EBV. The determining factors for development of EBV-related HL remain poorly understood, but likely involve immunological control of the viral infection. Accordingly, markers of the HLA class I region have been associated with risk of EBV-related HL. To study the host genetic component of EBV-related HL further, we investigated the lymphoma's association with HLA-A*01 and HLA-A*02 simultaneously in the setting of infectious mononucleosis (IM), a risk factor for EBV-related HL, in a case-series analysis including 278 EBV-related and 656 EBV-unrelated cases of HL. By logistic regression, HLA-A*01 alleles [odds ratio (OR) per allele, 2.15; 95% CI, 1.60-2.88] were associated with increased and HLA-A*02 alleles (OR per allele, 0.70; 95% CI, 0.51-0.97) with decreased risk of EBV-related HL. These allele-specific associations corresponded to nearly 10-fold variation in risk of EBV-related HL between HLA-A*01 and HLA-A*02 homozygotes. History of IM was also associated with risk of EBV-related HL (OR, 3.40; 95% CI, 1.74-6.66). The association between history of IM and EBV-related HL was not seen in the presence of HLA-A*02 because this allele appeared to neutralize the effect of IM on EBV-related HL risk. Our findings suggest that HLA class I-restricted EBV-specific cytotoxic T-cell responses and events in the early immune response to EBV infection in IM play critical roles in the pathogenesis of EBV-related HL.
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| 29. |
- Johansson, E, et al.
(författare)
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Carbon growth in diamond deposition on nickel studied in situ by soft x-ray emission spectroscopy
- 1996
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Ingår i: JOURNAL OF APPLIED PHYSICS. - : AMER INST PHYSICS. ; 79:9, s. 7248-7255
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- The initial stages of diamond growth on nickel have been studied by in situ electron-excited soft x-ray emission spectroscopy. The study has been able to clarify that the codeposition of ordered graphite at the substrate/film interface is due to carbon pr
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| 30. |
- Lossius, AH, et al.
(författare)
-
Shifts in the Skin Microbiota after UVB Treatment in Adult Atopic Dermatitis
- 2022
-
Ingår i: Dermatology (Basel, Switzerland). - : S. Karger AG. - 1421-9832 .- 1018-8665. ; 238:1, s. 109-120
-
Tidskriftsartikel (refereegranskat)abstract
- <b><i>Background:</i></b> The pathophysiology in atopic dermatitis (AD) is not fully understood, but immune dysfunction, skin barrier defects, and alterations of the skin microbiota are thought to play important roles. AD skin is frequently colonized with <i>Staphylococcus aureus</i> (<i>S. aureus</i>) and microbial diversity on lesional skin (LS) is reduced compared to on healthy skin. Treatment with narrow-band ultraviolet B (nb-UVB) leads to clinical improvement of the eczema and reduced abundance of <i>S. aureus</i>. However, in-depth knowledge of the temporal dynamics of the skin microbiota in AD in response to nb-UVB treatment is lacking and could provide important clues to decipher whether the microbial changes are primary drivers of the disease, or secondary to the inflammatory process. <b><i>Objectives:</i></b> To map the temporal shifts in the microbiota of the skin, nose, and throat in adult AD patients after nb-UVB treatment. <b><i>Methods:</i></b> Skin swabs were taken from lesional AD skin (<i>n</i> = 16) before and after 3 treatments of nb-UVB, and after 6–8 weeks of full-body treatment. We also obtained samples from non-lesional skin (NLS) and from the nose and throat. All samples were characterized by 16S rRNA gene sequencing. <b><i>Results:</i></b> We observed shifts towards higher diversity in the microbiota of lesional AD skin after 6–8 weeks of treatment, while the microbiota of NLS and of the nose/throat remained unchanged. After only 3 treatments with nb-UVB, there were no significant changes in the microbiota. <b><i>Conclusion:</i></b> Nb-UVB induces changes in the skin microbiota towards higher diversity, but the microbiota of the nose and throat are not altered.
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| 31. |
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| 32. |
- Ma, Y, et al.
(författare)
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Core excitons and vibronic coupling in diamond and graphite
- 1993
-
Ingår i: Physical Review Letters. - 0031-9007. ; 71:22, s. 3725-3728
-
Tidskriftsartikel (refereegranskat)abstract
- The C 1s exciton in diamond is studied by soft x-ray emission excited with high resolution monochromatic photons. A strong phonon sideband of 5 eV wide is observed in the exciton recombination spectrum. With the phonon contribution, the exciton binding energy is estimated to be 1.5 eV. The excited atom is suggested to undergo Jahn-Teller relaxation similar to that of the nitrogen impurities in diamond. A similar exciton is observed at the sigma*-band threshold in graphite. These results provide new insights to the understanding of the core exciton and the donor problem in diamond and other systems.
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| 33. |
- Nordgren, J, et al.
(författare)
-
Resonant soft X-ray fluorescence spectra of molecules
- 1997
-
Ingår i: Applied Physics A (Materials Science Processing). - 0947-8396. ; 65:2, s. 97-105
-
Tidskriftsartikel (refereegranskat)abstract
- A review is presented of some recent advancements in resonant soft X-ray fluorescence spectroscopy applied to molecules. The concept of inelastic scattering is discussed for molecules with an element of symmetry, which introduces degeneracy or near-degeneracy of core excited states. The potential of the symmetry selection rules associated with resonant X-ray fluorescence is illustrated in studies of electronic structure as well as molecular dynamics. The use of polarized photons for exciting X-ray emission is discussed, and examples are presented where anisotropy of X-ray emission provides more detailed information. A brief section discusses the experimental considerations relevant for the spectroscopic technique.
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| 34. |
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| 35. |
- Nyberg, Tomas, et al.
(författare)
-
Studies of reactive sputtering of multi-phase chromium nitride
- 1997
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Ingår i: JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS. - 0734-2101. ; 15:2, s. 248-252
-
Tidskriftsartikel (refereegranskat)abstract
- We have presented a model for reactive sputter deposition of two-phase materials. This model has been applied to reactive sputtering of chromium nitride where it is assumed that either Cr2N or CrN is formed. In order to test the validity of the model, a n
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| 36. |
- Skytt, P, et al.
(författare)
-
Angle-resolved soft-x-ray fluorescence and absorption study of graphite : Physical Review B (Condensed Matter)
- 1994
-
Ingår i: Physical Review B Condensed Matter. - 0163-1829 .- 1095-3795. ; 50:15
-
Tidskriftsartikel (refereegranskat)abstract
- The x-ray fluorescence and absorption of highly oriented pyrolytic graphite have been measured using monochromatic synchrotron radiation. The spectra can be separated into contributions from pi- and sigma-band components by measuring at different angles of incidence and at different emission angles. The shape of the x-ray fluorescence spectra varies dramatically with excitation energy near the C K edge. This dependence on excitation energy can be interpreted within a resonant-inelastic-scattering formalism. The results are compared with previously published band-structure calculations and photoemission results, and demonstrate the potential for using x-ray fluorescence to obtain symmetry-resolved band information.
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| 37. |
- SKYTT, P, et al.
(författare)
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IN-SITU MONITORING OF HFCVD DIAMOND GROWTH ON NICKEL USING SOFT-X-RAY EMISSION-SPECTROSCOPY
- 1995
-
Ingår i: VACUUM. - : PERGAMON-ELSEVIER SCIENCE LTD. - 0042-207X. ; 46:8-10, s. 1053-1054
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- It is well known that by analysing the C-K-emission from low pressure grown diamond films that it is possible to extract information of the types of bonding present. A HFCVD reactor has been constructed which together with a small soft X-ray emission spec
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| 38. |
- Skytt, P, et al.
(författare)
-
Lifetime-vibrational interference effects in the resonantly excited x-ray-emission spectra of CO
- 1997
-
Ingår i: Physical Review A. Atomic, Molecular, and Optical Physics. - 1050-2947. ; 55:1, s. 146-154
-
Tidskriftsartikel (refereegranskat)abstract
- A systematic study of vibrational band profiles in resonantly excited x-ray-emission spectra of free molecules is made. Carbon and oxygen K-emission spectra of CO following core excitations, using narrow-bandpass synchrotron radiation, to the 2 pi orbital an presented. Because of the short lifetime of the core-excited states, interference effects between close-lying coherently excited vibrational levels may occur. The importance of lifetime-vibrational interference in the carbon and oxygen x-ray-emission spectra is investigated by comparing the experimental band profiles with simulated profiles. It is shown that to properly describe the band profiles in the oxygen emission spectra it is necessary to include the interference contributions, while in the carbon spectra the interference contributions are important only when the excitation energy is tuned towards higher vibrational levels. For example, when the excitation energy is tuned to the upsilon=2 vibrational level significant interference effects are observed. It is also demonstrated how emission spectra recorded with a detuning of the excitation energy from the resonance can be used to check the shape of the photon distribution of the synchrotron radiation.
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| 39. |
- SKYTT, P, et al.
(författare)
-
PROBING SYMMETRY-BREAKING UPON CORE EXCITATION WITH RESONANT X-RAY-FLUORESCENCE
- 1995
-
Ingår i: PHYSICAL REVIEW A. - : AMER INST PHYSICS. - 1050-2947. ; 52:5, s. 3572-3576
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Resonantly excited x-ray fluorescence spectra of the benzene molecule are presented and analyzed in terms of symmetry-selective resonant scattering processes. The sharp frequency dependency that is observed can be understood from strict parity and symmetr
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| 40. |
- Skytt, P, et al.
(författare)
-
Quenching of symmetry breaking in resonant inelastic X-ray scattering by detuned excitation
- 1996
-
Ingår i: Physical Review Letters. - 0031-9007. ; 77:25, s. 5035-5038
-
Tidskriftsartikel (refereegranskat)abstract
- Observations made in oxygen K emission of CO2 show that the symmetry selective character of resonant x-ray emission is excitation energy dependent. Electronically dipole forbidden O K emission lines are observed for excitation at the O 1s --> pi* resonance, and they are gradually reduced upon detuning the excitation energy below threshold. The occurrence of forbidden transitions is explained in terms of dynamical symmetry breaking due to vibronic coupling, and the observation of quenching of the symmetry breaking upon detuning as due to an effective quenching of this vibronic coupling. Scattering theory applied to a few-level system is shown to account for the energy dependence of the symmetry selection in the limit of narrow bandpass photon excitation.
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| 41. |
- Skytt, P, et al.
(författare)
-
Role of screening and angular distributions in resonant x-ray emission of CO
- 1997
-
Ingår i: Physical Review A. Atomic, Molecular, and Optical Physics. - 1050-2947. ; 55:1, s. 134-145
-
Tidskriftsartikel (refereegranskat)abstract
- Resonantly excited carbon and oxygen x-ray-emission spectra of gaseous carbon monoxide are presented. Emission spectra obtained with selective excitation to the pi* valence orbital and to various Rydberg levels are compared to satellite-free nonresonant spectra. Screening effects caused by the excited electron, creating energy shifts and intensity variations in the resonant spectra compared to the nonresonant spectra, are observed, as well as an angular dependence of the resonantly excited spectra. The experimental spectra are compared to simulated spectra where the vibronic part is computed by means of a lifetime-vibrational interference formalism. The electronic intensities are analyzed by a separate-state, self-consistent-held method and a formalism for resonant inelastic x-ray scattering, focusing On screening and angular dependence.
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| 42. |
- YI, L, et al.
(författare)
-
SYMMETRY-SELECTIVE RESONANT INELASTIC X-RAY-SCATTERING OF C-60
- 1995
-
Ingår i: PHYSICAL REVIEW B-CONDENSED MATTER. - : AMER INST PHYSICS. - 0163-1829. ; 52:20, s. 14479-14496
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- The resonantly excited x-ray emission spectra of the C-60 molecule are presented and analyzed in terms of symmetry- and polarization-selective resonant inelastic scattering processes (RIXS). The theoretical analysis implements recently derived formalisms
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