| 11. |
- Borne, Kurtis D., et al.
(författare)
-
Ultrafast electronic relaxation pathways of the molecular photoswitch quadricyclane
- 2024
-
Ingår i: NATURE CHEMISTRY. - 1755-4330 .- 1755-4349. ; 16, s. 499-505
-
Tidskriftsartikel (refereegranskat)abstract
- The light-induced ultrafast switching between molecular isomers norbornadiene and quadricyclane can reversibly store and release a substantial amount of chemical energy. Prior work observed signatures of ultrafast molecular dynamics in both isomers upon ultraviolet excitation but could not follow the electronic relaxation all the way back to the ground state experimentally. Here we study the electronic relaxation of quadricyclane after exciting in the ultraviolet (201 nanometres) using time-resolved gas-phase extreme ultraviolet photoelectron spectroscopy combined with non-adiabatic molecular dynamics simulations. We identify two competing pathways by which electronically excited quadricyclane molecules relax to the electronic ground state. The fast pathway (<100 femtoseconds) is distinguished by effective coupling to valence electronic states, while the slow pathway involves initial motions across Rydberg states and takes several hundred femtoseconds. Both pathways facilitate interconversion between the two isomers, albeit on different timescales, and we predict that the branching ratio of norbornadiene/quadricyclane products immediately after returning to the electronic ground state is approximately 3:2.
|
|
| 12. |
- Borné, Yan, et al.
(författare)
-
Genome wide association study identifies two loci associated with cadmium in erythrocytes among never-smokers
- 2016
-
Ingår i: Hum Mol Genet. - : Oxford University Press (OUP). - 0964-6906 .- 1460-2083. ; 25:11, s. 2342-2348
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Cadmium is a non-essential toxic metal with multiple adverse health effects. Exposure in the general population occurs by smoking and diet. Cadmium in erythrocytes is a valid biomarker of exposure and body burden of cadmium. Objectives: We aimed to identify genetic variants related to concentrations of cadmium in erythrocytes. Methods: Erythrocyte cadmium was analyzed in 4432 individuals (1728 never smokers) from the Swedish population-based Malmo Diet and Cancer cohort. Genotyping was performed using the Illumina HumanOmniExpressExome Bead chip with genome-wide coverage. Genome wide analyses were performed in the whole sample and in never smokers. Results: No single nucleotide polymorphism (SNP) reached a genome-wide significant association with erythrocyte cadmium in the whole sample. However, in never smokers, 14 variants showed genome-wide significant relationships with erythrocyte cadmium after adjusting for age and sex. Thirteen variants were in linkage disequilibrium on chromosome 8q13.3 in the XKR9 and LACTB2 genes. The lead SNP on 8q13.3 was rs12681420 (minor allele G, minor allele frequency [MAF] = 0.46, beta: -0.11, P = 3.48 x 10(-11)), an intron variant within the XKR9 gene. The other significant locus, rs17574271 (minor allele C, MAF = 0.09, beta: 0.17, P = 6.18 x 10(-9)), was an intron variant within the DLGAP1 gene at chromosome 18p11.31. Conclusion: This genome-wide study of never smokers from the general population identified two independent regions related to erythrocyte cadmium. The strongest locus covers the XKR9 and LACTB2 genes, which both could have related functions in cadmium absorption and metabolism. Replication studies are needed to confirm the findings and mechanisms should be further investigated.
|
|
| 13. |
- Caboi, F, et al.
(författare)
-
Lipase action on a monoolein/sodium oleate aqueous cubic liquid crystalline phase - a NMR and X-ray diffraction study
- 2002
-
Ingår i: Colloids and Surfaces B: Biointerfaces. - 1873-4367. ; 26:1-2, s. 159-171
-
Tidskriftsartikel (refereegranskat)abstract
- The effect of adding Thermomyces (formerly Humicola) lanuginosa lipase (TLL) to a monoolein (MO)/sodium oleate (NaO) aqueous cubic liquid crystalline phase has been studied. H-1-NMR, C-13-NMR, H-1-PGSE (Pulsed-magnetic field Gradient Spin-Echo) self-diffusion measurements, and Small Angle X-ray Diffraction were used to follow the degradation of the cubic phase. The reaction sequence in terms of phase transitions follows the order bicontinuous cubic --> reverse hexagonal --> micellar cubic --> micellar phase and corresponds to the previously determined phase diagrams. These changes correlate with changes in the lipid composition observed by C-13-NMR and confirmed by HPLC analysis. The initial decrease of the diffusion coefficients of water and lipid can be related to the transformation of the bicontinuous cubic phase to a reverse hexagonal structure. (C) 2002 Elsevier Science B.V. All rights reserved.
|
|
| 14. |
|
|
| 15. |
|
|
| 16. |
|
|
| 17. |
- Urquiza-González, M., et al.
(författare)
-
Benchmark evaluation for a single frequency continuous wave OPO seeded pulsed dye amplifier for high-resolution laser spectroscopy
- 2023
-
Ingår i: Proceedings of SPIE - The International Society for Optical Engineering. - : SPIE. - 0277-786X .- 1996-756X. - 9781510659032
-
Konferensbidrag (refereegranskat)abstract
- The study of the atomic spectrum via resonant laser excitation provides access to underlying effects caused by the nuclear structure, which is of special interest in short-lived radioisotopes produced at Isotope Separator On-Line (ISOL) facilities. Current implementations of resonant laser ionization techniques often limit the extraction of the nuclear observables due to the low spectral resolution of the pulsed laser systems deployed. Several high-resolution spectroscopy techniques demand spectral widths in the order of hundreds of MHz and below. A proven solution to reduce this linewidth is the pulsed amplification of a narrow-band continuous wave (cw) laser. This work presents the demonstration of a pulsed dye amplifier seeded by a commercially available cw Optical Parametric Oscillator (OPO). The performance of this system was compared with competing setups using a cw dye laser seed source as well as a frequency mixing technique using a combination of an injection-locked titanium:sapphire (Ti:Sa) and a Nd:YVO4 laser. Spectral bandwidths of the systems were measured using a high finesse Fabry-Perot Interferometer, resulting in comparable optical linewidths between 140 to 156 MHz at a wavelength of 328 nm for the different laser setups. Suitability for on-line experiments was validated by performing high-resolution spectroscopy of radioactive silver isotopes in the Collinear Resonance Ionization Spectroscopy (CRIS) experiment at the Isotope Separator On-Line Device (ISOLDE), at the European Organization for Nuclear Research (CERN). The quality of the hyperfine spectra was similar for the dye and the OPO seed and the deduced hyperfine splitting was in good agreement with literature, while the frequency mixing technique exhibited less precise results attributed to the frequency instabilities and mode-hops of the single-mode Nd:YVO4 laser.
|
|
| 18. |
- Wu, Chuanyan, et al.
(författare)
-
Elevated circulating follistatin associates with an increased risk of type 2 diabetes
- 2021
-
Ingår i: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 12, s. 1-10
-
Tidskriftsartikel (refereegranskat)abstract
- The hepatokine follistatin is elevated in patients with type 2 diabetes (T2D) and promotes hyperglycemia in mice. Here we explore the relationship of plasma follistatin levels with incident T2D and mechanisms involved. Adjusted hazard ratio (HR) per standard deviation (SD) increase in follistatin levels for T2D is 1.24 (CI: 1.04-1.47, p < 0.05) during 19-year follow-up (n = 4060, Sweden); and 1.31 (CI: 1.09-1.58, p < 0.01) during 4-year follow-up (n = 883, Finland). High circulating follistatin associates with adipose tissue insulin resistance and non-alcoholic fatty liver disease (n = 210, Germany). In human adipocytes, follistatin dose-dependently increases free fatty acid release. In genome-wide association study (GWAS), variation in the glucokinase regulatory protein gene (GCKR) associates with plasma follistatin levels (n = 4239, Sweden; n = 885, UK, Italy and Sweden) and GCKR regulates follistatin secretion in hepatocytes in vitro. Our findings suggest that GCKR regulates follistatin secretion and that elevated circulating follistatin associates with an increased risk of T2D by inducing adipose tissue insulin resistance.
|
|
