1. |
- Aad, G., et al.
(author)
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- 2011
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Journal article (peer-reviewed)
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2. |
- Fernandez-Garcia, J. P., et al.
(author)
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11Li Breakup on 208Pb at Energies Around the Coulomb Barrier
- 2013
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In: Physical Review Letters. - 1079-7114 .- 0031-9007. ; 110:14
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Journal article (peer-reviewed)abstract
- The inclusive breakup for the Li-11 + Pb-208 reaction at energies around the Coulomb barrier has been measured for the first time. A sizable yield of Li-9 following the Li-11 dissociation has been observed, even at energies well below the Coulomb barrier. Using the first-order semiclassical perturbation theory of Coulomb excitation it is shown that the breakup probability data measured at small angles can be used to extract effective breakup energy as well as the slope of B(E1) distribution close to the threshold. Four-body continuum-discretized coupled-channels calculations, including both nuclear and Coulomb couplings between the target and projectile to all orders, reproduce the measured inclusive breakup cross sections and support the presence of a dipole resonance in the Li-11 continuum at low excitation energy.
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3. |
- Fernandez-Garcia, J. P., et al.
(author)
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Study of the break-up channel in 11Li+208Pb collisions at energies around the Coulomb barrier
- 2014
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In: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 515:1
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Conference paper (peer-reviewed)abstract
- We present a study of 11Li+208Pb collisions at energies around the Coulomb barrier (Elab 24.3 and 29.8 MeV), measured at the post-accelerated beam facility, ISAC II, at TRIUMF (Vancouver, Canada). A remarkably large yield of 9Li has been observed, a result that is attributed to the weak binding of the 11Li nucleus. The angular distribution of this 9Li yield, relative to the elastic one, has been analysed in terms of first-order semiclassical calculations as well as four-body and three-body Continuum-Discretized Coupled-Channels (CDCC) calculations, based on a three-body and di-neutron model of the 11Li nucleus, respectively. The calculations reproduce well the trend of the data and support the existence of a large concentration of B(E1) strength at very low excitation energies. The connection of this large B(E1) with a possible low-lying dipole resonance is discussed. © Published under licence by IOP Publishing Ltd.
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4. |
- Borge, M. J. G., et al.
(author)
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Scattering of the halo nucleus 11Li and its core 9Li on 208Pb at energies around the Coulomb barrier
- 2012
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In: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 381:1, s. Art. no. 012085-
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Conference paper (peer-reviewed)abstract
- The first measurement of the elastic scattering of the halo nucleus 11Li and its core 9Li on 208Pb at energies around the Coulomb barrier is presented. The 11Li reaction showed a large cross section for the breakup channel, even at energies well below the barrier. The analysis of the 11Li + 208Pb scattering data in terms of the continuum-discretized coupled-channel calculations indicates that the effect of the coupling to the breakup channels produces a strong suppression of the elastic cross section at energies above and below the barrier. This effect is mainly due to the strong Coulomb coupling to the dipole states in the low-lying continuum of 11Li.
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5. |
- Cubero, M., et al.
(author)
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Do Halo Nuclei Follow Rutherford Elastic Scattering at Energies Below the Barrier? The Case of 11Li
- 2012
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In: Physical Review Letters. - 1079-7114 .- 0031-9007. ; 109:26
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Journal article (peer-reviewed)abstract
- The first measurement of the elastic scattering of the halo nucleus 11Li and its core 9Li on 208Pb at energies near the Coulomb barrier is presented. The 11Li+208Pb elastic scattering shows a strong reduction with respect to the Rutherford cross section, even at energies well below the barrier and down to very small scattering angles. This drastic change of the elastic differential cross section observed in 11Li+208Pb is the consequence of the halo structure of 11Li, as it is not observed in the elastic scattering of its core 9Li at the same energies. Four-body continuum-discretized coupled-channels calculations, based on a three-body model of the 11Li projectile, are found to explain the measured angular distributions and confirm that the observed reduction is mainly due to the strong Coulomb coupling to the dipole states in the low-lying continuum of 11Li. These calculations suggest the presence of a low-lying dipole resonance in 11Li close to the breakup threshold.
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6. |
- Borge, M. J. G., et al.
(author)
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Scattering of the halo nucleus Li-11 and its core Li-9 on Pb-208 at energies around the Coulomb barrier
- 2012
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In: Journal of Physics: Conference Series. - 1742-6588 .- 1742-6596. ; 381
-
Conference paper (peer-reviewed)abstract
- The first measurement of the elastic scattering of the halo nucleus Li-11 and its core Li-9 on Pb-208 at energies around the Coulomb barrier is presented. The Li-11 reaction showed a large cross section for the breakup channel, even at energies well below the barrier. The analysis of the Li-11 + Pb-208 scattering data in terms of the continuum-discretized coupled-channel calculations indicates that the effect of the coupling to the breakup channels produces a strong suppression of the elastic cross section at energies above and below the barrier. This effect is mainly due to the strong Coulomb coupling to the dipole states in the low-lying continuum of Li-11.
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7. |
- Cubero, M., et al.
(author)
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Elastic scattering of 9Li on 208Pb at energies around the Coulomb barrier
- 2011
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In: AIP Conference Proceedings. - : AIP. - 1551-7616 .- 0094-243X. - 9780735409378 ; 1377, s. 338-340
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Conference paper (peer-reviewed)abstract
- We have studied the dynamical effects of the halo structure of 11Li on the scattering on heavy targets at energies around the Coulomb barrier. This experiment was performed at ISAC‐II at TRIUMF with a world record in production of the post‐accelerated 11Li beam. As part of this study we report here on the first measurement of the elastic cross section of the core nucleus, i.e. 9Li on 208Pb, at energies around the Coulomb barrier. A preliminary optical model analysis has been performed in order to extract a global optical potential to describe the measured angular distributions.
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8. |
- Cubero, M., et al.
(author)
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Scattering of 9Li on 208Pb at energies around the Coulomb barrier
- 2011
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In: EPJ Web of Conferences. - : EDP Sciences. - 2101-6275 .- 2100-014X. - 9782759806935 ; 17, s. Art. no. 16002-
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Conference paper (peer-reviewed)abstract
- In order to study the dynamics of 11Li and 9Li beams in a strong electric field at energies around the Coulomb barrier, we measured at the ISACII-TRIUMF Facility the angular distribution of elastic and inelastic scattering of 11Li+208Pb at 24.2 and 29.7 MeV and 9Li+208Pb at 24, 29.5 and 33 MeV laboratory energies. We present here the first determination of the angular distribution of the cross section of 9Li+208Pb. The results are compared with theoretical calculations using the double-folding São Paulo Potential (SPP) for the real part and a for the imaginary part a Woods-Saxon potential. A good overall agreement is obtained.
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9. |
- Gustafsson, T., et al.
(author)
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Effects of 3 days unloading on molecular regulators of muscle size in humans
- 2010
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In: Journal of applied physiology. - : American Physiological Society. - 8750-7587 .- 1522-1601. ; 109:3, s. 721-727
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Journal article (peer-reviewed)abstract
- Gustafsson T, Osterlund T, Flanagan JN, von Walden F, Trappe TA, Linnehan RM, Tesch PA. Effects of 3 days unloading on molecular regulators of muscle size in humans. J Appl Physiol 109: 721-727, 2010. First published June 10, 2010; doi: 10.1152/japplphysiol.00110.2009.-Changes in skeletal muscle mass are controlled by mechanisms that dictate protein synthesis or degradation. The current human study explored whether changes in activation of the phosphoinositide 3-kinase (PI3K)-Akt1, p38, myostatin, and mRNA expression of markers of protein degradation and synthesis occur soon after withdrawal of weight bearing. Biopsies of the vastus lateralis muscle (VL) and soleus muscle (Sol) were obtained from eight healthy men before and following 3 days of unilateral lower limb suspension (ULLS). Akt1, Forkhead box class O (FOXO)-1A, FOXO-3A, p38, and eukaryotic translation initiation factor 4E binding protein 1 (4E-BP1) phosphorylation and protein levels and myostatin protein level were analyzed by Western blot. Levels of mRNA of IGF1, FOXO-1A, FOXO-3A, atrogin-1, MuRF-1, caspase-3, calpain-2, calpain-3, 4E-BP1, and myostatin were measured using real-time PCR. The amounts of phosphorylated Akt1, FOXO-1A, FOXO-3A, and p38 were unaltered (P > 0.05) after ULLS. Similarly, mRNA levels of IGF1, FOXO-1A, FOXO-3A, caspase-3, calpain-2, and calpain-3 showed no changes (P > 0.05). The mRNA levels of atrogin-1 and MuRF-1, as well as the mRNA and protein phosphorylation of 4E-BP1, increased (P < 0.05) in VL but not in Sol. Both muscles showed increased (P < 0.05) myostatin mRNA and protein following ULLS. These results suggest that pathways other than PI3K-Akt stimulate atrogin-1 and MuRF-1 expression within 3 days of ULLS. Alternatively, transient changes in these pathways occurred in the early phase of ULLS. The increased myostatin mRNA and protein expression also indicate that multiple processes are involved in the early phase of muscle wasting. Further, the reported difference in gene expression pattern across muscles suggests that mechanisms regulating protein content in human skeletal muscle are influenced by phenotype and/or function.
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10. |
- Petrovic, Natasa, et al.
(author)
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Chronic Perixosome Proliferator-activated Receptor gamma (PPARgamma) activation of epididymally derived white adipocyte cultures reveals a population of thermogenically competent, UCP1-containing adipocytes molecularly distinct from classical brown adipocytes.
- 2010
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In: Journal of Biological Chemistry. - 0021-9258 .- 1083-351X. ; 285:10, s. 7153-7164
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Journal article (peer-reviewed)abstract
- The recent insight that brown adipocytes and muscle cells share a common origin and in this respect are distinct from white adipocytes has spurred questions concerning the origin and molecular characteristics of the UCP1-expressing cells observed in classical white adipose tissue depots under certain physiological or pharmacological conditions. Examining precursors from the purest white adipose tissue depot (epididymal), we report here that chronic treatment with the PPARgamma agonist rosiglitazone promotes not only the expression of PGC-1alpha and mitochondriogenesis in these cells but also a norepinephrine-augmentable UCP1 gene expression in a significant subset of the cells, providing these cells with a genuine thermogenic capacity. However, although functional thermogenic genes are expressed, the cells are devoid of transcripts for the novel transcription factors now associated with classical brown adipocytes (Zic1, Lhx8, Meox2 and characteristically PRDM16) or for myocyte-associated genes (myogenin and myomirs (muscle-specific microRNAs)) and retain white-fat characteristics such as Hoxc9 expression. Co-culture experiments verify that the UCP1-expressing cells are not proliferating classical brown adipocytes (adipomyocytes) and these cells therefore constitute a subset of adipocytes (''brite'' adipocytes) with a developmental origin and molecular characteristics distinguishing them as a separate class of cells.
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