| 11. |
- Ali, Alaa M. G., et al.
(författare)
-
Alcohol Consumption and Survival after a Breast Cancer Diagnosis: A Literature-Based Meta-analysis and Collaborative Analysis of Data for 29,239 Cases
- 2014
-
Ingår i: Cancer Epidemiology Biomarkers & Prevention. - 1538-7755 .- 1055-9965. ; 23:6, s. 934-945
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Evidence for an association of alcohol consumption with prognosis after a diagnosis of breast cancer has been inconsistent. We have reviewed and summarized the published evidence and evaluated the association using individual patient data from multiple case cohorts. Methods: A MEDLINE search to identify studies published up to January 2013 was performed. We combined published estimates of survival time for "moderate drinkers" versus nondrinkers. An analysis of individual participant data using Cox regression was carried out using data from 11 case cohorts. Results: We identified 11 published studies suitable for inclusion in the meta-analysis. Moderate postdiagnosis alcohol consumption was not associated with overall survival [HR, 0.95; 95% confidence interval (CI), 0.85-1.05], but there was some evidence of better survival associated with prediagnosis consumption (HR, 0.80; 95% CI, 0.73-0.88). Individual data on alcohol consumption for 29,239 cases with 4,839 deaths were available from the 11 case cohorts, all of which had data on estrogen receptor (ER) status. For women with ER-positive disease, there was little evidence that pre-or postdiagnosis alcohol consumption is associated with breast cancer-specific mortality, with some evidence of a negative association with all-cause mortality. On the basis of a single study, moderate postdiagnosis alcohol intake was associated with a small reduction in breast cancer-specific mortality for women with ER-negative disease. There was no association with prediagnosis intake for women with ER-negative disease. Conclusion: There was little evidence that pre- or post-diagnosis alcohol consumption is associated with breast cancer-specific mortality for women with ER-positive disease. There was weak evidence that moderate post-diagnosis alcohol intake is associated with a small reduction in breast cancer-specific mortality in ER-negative disease. Impact: Considering the totality of the evidence, moderate postdiagnosis alcohol consumption is unlikely to have a major adverse effect on the survival of women with breast cancer. (C) 2014 AACR.
|
|
| 12. |
- Horio, M., et al.
(författare)
-
Two-dimensional type-II Dirac fermions in layered oxides
- 2018
-
Ingår i: Nature Communications. - : NATURE PUBLISHING GROUP. - 2041-1723. ; 9
-
Tidskriftsartikel (refereegranskat)abstract
- Relativistic massless Dirac fermions can be probed with high-energy physics experiments, but appear also as low-energy quasi-particle excitations in electronic band structures. In condensed matter systems, their massless nature can be protected by crystal symmetries. Classification of such symmetry-protected relativistic band degeneracies has been fruitful, although many of the predicted quasi-particles still await their experimental discovery. Here we reveal, using angle-resolved photoemission spectroscopy, the existence of two-dimensional type-II Dirac fermions in the high-temperature superconductor La1.77Sr0.23CuO4. The Dirac point, constituting the crossing of d(x2-y2) and d(z2) bands, is found approximately one electronvolt below the Fermi level (E-F) and is protected by mirror symmetry. If spin-orbit coupling is considered, the Dirac point degeneracy is lifted and the bands acquire a topologically non-trivial character. In certain nickelate systems, band structure calculations suggest that the same type-II Dirac fermions can be realised near EF.
|
|
| 13. |
- Matt, C. E., et al.
(författare)
-
Direct observation of orbital hybridisation in a cuprate superconductor
- 2018
-
Ingår i: Nature Communications. - : Nature Publishing Group. - 2041-1723. ; 9
-
Tidskriftsartikel (refereegranskat)abstract
- The minimal ingredients to explain the essential physics of layered copper-oxide (cuprates) materials remains heavily debated. Effective low-energy single-band models of the copper-oxygen orbitals are widely used because there exists no strong experimental evidence supporting multi-band structures. Here, we report angle-resolved photoelectron spectroscopy experiments on La-based cuprates that provide direct observation of a two-band structure. This electronic structure, qualitatively consistent with density functional theory, is parametrised by a two-orbital (d(x2-y2) and d(z2)) tight-binding model. We quantify the orbital hybridisation which provides an explanation for the Fermi surface topology and the proximity of the van-Hove singularity to the Fermi level. Our analysis leads to a unification of electronic hopping parameters for single-layer cuprates and we conclude that hybridisation, restraining d-wave pairing, is an important optimisation element for superconductivity.
|
|
| 14. |
- von Arx, K., et al.
(författare)
-
Resonant inelastic x-ray scattering study of Ca3Ru2O7
- 2020
-
Ingår i: Physical Review B. - 2469-9969 .- 2469-9950. ; 102:23
-
Tidskriftsartikel (refereegranskat)abstract
- We present a combined oxygen K-edge x-ray absorption spectroscopy and resonant inelastic x-ray scattering (RIXS) study of the bilayer ruthenate Ca3Ru2O7. Our RIXS experiments on Ca3Ru2O7 were carried out on the overlapping planar and interplanar oxygen resonances, which are distinguishable from the apical one. Comparison to equivalent oxygen K-edge spectra recorded on band-Mott insulating Ca2RuO4 is made. In contrast to Ca2RuO4 spectra, which contain excitations linked to Mott physics, Ca3Ru2O7 spectra feature only intra-t(2g) ones that do not directly involve the Coulomb energy scale. As found in Ca2RuO4, we resolve two intra-t(2g) excitations in Ca3Ru2O7. Moreover, the lowest lying excitation in Ca3Ru2O7 shows a significant dispersion, revealing a collective character different from what is observed in Ca2RuO4. Theoretical modeling supports the interpretation of this lowest energy excitation in Ca3Ru2O7 as a magnetic transverse mode with multiparticle character, whereas the corresponding excitation in Ca2RuO4 is assigned to combined longitudinal and transverse spin modes. These fundamental differences are discussed in terms of the inequivalent magnetic ground-state manifestations in Ca2RuO4 and Ca3Ru2O7.
|
|
| 15. |
- Wang, Qisi, et al.
(författare)
-
Magnon interactions in a moderately correlated Mott insulator
- 2024
-
Ingår i: Nature Communications. - : Springer Nature. - 2041-1723. ; 15:1
-
Tidskriftsartikel (refereegranskat)abstract
- Quantum fluctuations in low-dimensional systems and near quantum phase transitions have significant influences on material properties. Yet, it is difficult to experimentally gauge the strength and importance of quantum fluctuations. Here we provide a resonant inelastic x-ray scattering study of magnon excitations in Mott insulating cuprates. From the thin film of SrCuO2, single- and bi-magnon dispersions are derived. Using an effective Heisenberg Hamiltonian generated from the Hubbard model, we show that the single-magnon dispersion is only described satisfactorily when including significant quantum corrections stemming from magnon-magnon interactions. Comparative results on La2CuO4 indicate that quantum fluctuations are much stronger in SrCuO2 suggesting closer proximity to a magnetic quantum critical point. Monte Carlo calculations reveal that other magnetic orders may compete with the antiferromagnetic Néel order as the ground state. Our results indicate that SrCuO2—due to strong quantum fluctuations—is a unique starting point for the exploration of novel magnetic ground states.
|
|
