| 1. |
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| 2. |
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| 3. |
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| 4. |
- Fäldt, Göran, et al.
(författare)
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Comparison of the pp → π+pn and pp → π+d production rates
- 2017
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Ingår i: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 770, s. 146-148
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Tidskriftsartikel (refereegranskat)abstract
- Fully constrained bubble chamber data on the pp -> pi(+)pn and pp -> pi(+)d reactions are used to investigate the ratio of the counting rates for the two processes at low pn excitation energies. Whereas the ratio is in tolerable agreement with that found in a high resolution spectrometer experiment, the angular distribution in the final pn rest frame shows that the deviation from the predictions of final state interaction theory must originate primarily from higher partial waves in the pn system. These considerations might also be significant for the determination of the S -wave Ap scattering length from data on the pp -> K+Lambda p reaction.
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| 5. |
- Fäldt, Göran, et al.
(författare)
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Coulomb-nuclear interference in pion-nucleus bremsstrahlung
- 2009
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Ingår i: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 79:1, s. 014607-
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Tidskriftsartikel (refereegranskat)abstract
- Pion-nucleus bremsstrahlung offers a possibility of measuring the structure functions of pion-Compton scattering from a study of the small-momentum-transfer region where the bremsstrahlung reaction is dominated by the single-photon-exchange mechanism. The corresponding cross-section distribution is characterized by a sharp peak at small momentum transfers. But there is also a hadronic contribution that is smooth and constitutes an undesired background. In this article the modification of the single-photon-exchange amplitude by multiple Coulomb scattering is investigated as well as the Coulomb-nuclear interference term.
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| 6. |
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| 7. |
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| 8. |
- Fäldt, Göran
(författare)
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Entanglement in joint Lambda(Lambda)over-bar decay
- 2015
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Ingår i: European Physical Journal A. - : Springer Science and Business Media LLC. - 1434-6001 .- 1434-601X. ; 51:7
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Tidskriftsartikel (refereegranskat)abstract
- We investigate the joint decay in the reaction . This reaction may provide information on the electromagnetic form factors of the Lambda baryon, in the time-like region. We present a conventional diagram-based calculation where production and decay steps are coherent and summations over final-state proton and anti-proton spins are performed. The resulting cross-section distribution is explicitly covariant as it is expressed in scalar products of the four-momentum vectors of the participating particles. We compare this calculation with that of the folding method which we extend and make explicitly covariant. In the folding method production and decay distributions, not amplitudes, are folded together. Of particular importance is then a correct counting of the number of possible intermediate-hyperon-spin states.
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| 9. |
- Fäldt, Göran
(författare)
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Entanglement in joint Lambda(Lambda)over-bar decay; con
- 2022
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Ingår i: European Physical Journal A. - : Springer Nature. - 1434-6001 .- 1434-601X. ; 58:11
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Tidskriftsartikel (refereegranskat)abstract
- We have previously investigated joint AA decay in the reaction e(+)e(-) -> gamma Lambda(-> p pi(-))(Lambda) over bar(-> (p) over bar pi(+)). The cross-section-distribution functions encountered were relativistically covariant and expressed in terms of scalar products of the four-momentum vectors of the particles involved. In the present, sequel investigation, we work instead in the Lambda(Lambda) over bar rest system and with three-momentum scalars. In this configuration our results become directly comparable to those of others, including experiment.
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| 10. |
- Fäldt, Göran, et al.
(författare)
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Estimation of the ratio of the pn -> pn pi(0)pi(0)/pn -> d pi(0)pi(0) cross sections
- 2011
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Ingår i: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 701:5, s. 619-622
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Tidskriftsartikel (refereegranskat)abstract
- Evidence has recently been presented for the existence of a dibaryon of mass 2380 MeV/c(2) and width 70 MeV/c(2), which decays strongly into the d pi(0)pi(0) channel [M. Bashkanov, et al., Phys. Rev. Lett. 102 (2009) 052301; P. Adlarson, et al., arXiv:1104.0123]. The decay rate of such a hypothesised dibaryon into the {pn}i=0 pi(0)pi(0) channel is estimated in a weakly model-dependent way by using final state interaction theory. It is shown that, if the resonance exists, it should show up as strongly in this channel as in d pi(0)pi(0). The sum of the two decay modes would saturate most of the inelasticity predicted in the relevant partial waves in the 2380 MeV/c(2) region.
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| 11. |
- Fäldt, Göran, et al.
(författare)
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Extraction of parameters from final state interactions
- 2017
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Ingår i: PHYSICAL REVIEW C. - : AMER PHYSICAL SOC. - 2469-9985. ; 95:2
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Forskningsöversikt (refereegranskat)abstract
- It is argued that final state enhancements in production reactions at large momentum transfers, such as pp -> K+ Lambda p, are primarily sensitive to the position of a virtual bound state pole in the Lambda p system rather than the Lambda p scattering length and effective range. These arguments are supported by a study of the dispersion relation derived to describe such processes as a function of the cut-off energy. This shows that the position of the virtual bound state is independent of the cut-off energy.
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| 12. |
- Fäldt, Göran, et al.
(författare)
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Hadronic structure functions in the e(+) e(-) -> (Lambda)over-bar Lambda reaction
- 2017
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Ingår i: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 772, s. 16-20
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Tidskriftsartikel (refereegranskat)abstract
- Cross-section distributions are calculated for the reaction e(+)e(-) -> J/psi -> (Lambda) over bar(-> (p) over bar pi(+)) Lambda(-> p pi(-)), and related annihilation reactions mediated by vector mesons. The hyperon-decay distributions depend on a number of structure functions that are bilinear in the, possibly complex, psionic form factors G(M)(psi) and G(E)(psi) of the Lambda hyperon. The relative size and relative phase of these form factors can be uniquely determined from the unpolarized joint-decay distributions of the Lambda and anti-Lambda hyperons. Also the decay-asymmetry parameters of Lambda and anti-Lambda hyperons can be determined.
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| 13. |
- Fäldt, Göran, et al.
(författare)
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Hard pion bremsstrahlung in the Coulomb region
- 2007
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Ingår i: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 76:6, s. 064607.1-064607.7
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Tidskriftsartikel (refereegranskat)abstract
- Hard high-energy pion-nucleus bremsstrahlung, π − + A → π − + γ + A, is studied in the Coulomb region,i.e., the small-angle region where the nuclear scattering is dominated by the Coulomb interaction. Special attentionis focussed on the possibility of measuring the pion polarizability in such reactions. We study the sensitivity tothe structure of the underlying pion-Compton amplitude through a model with σ, ρ, and a1 exchanges. It is foundthat the effective energy in the virtual pion-Compton scattering is often so large that the threshold approximationdoes not apply.
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| 14. |
- Fäldt, Göran
(författare)
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Meson production in high-energy electron-nucleus scattering
- 2012
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Ingår i: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 86:2, s. 024611-
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Tidskriftsartikel (refereegranskat)abstract
- Pseudoscalar mesons can be produced and studied in high-energy electron-nucleus scattering. We review and extend our previous theoretical analysis of meson production in the nuclear Coulomb field. The P -> gamma gamma decay rates are most directly determined for mesons produced in the double-Coulomb region where both photons are nearly real, and provided the hadronic-background contributions remain small. The larger the mass of the meson the higher the electron energy needed to assure such favorable conditions.
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| 15. |
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| 16. |
- Fäldt, Göran, et al.
(författare)
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Phenomenological study of the pp -> pi(+) pn reaction
- 2018
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Ingår i: Physical Review C. - : AMER PHYSICAL SOC. - 2469-9985 .- 2469-9993. ; 97:2
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Tidskriftsartikel (refereegranskat)abstract
- Fully constrained bubble chamber data on the pp -> pi(+) pn and pp -> pi(+) d reactions are used to investigate the ratio of the counting rates for the two processes as function of the pn excitation energy Q. Though it is important to include effects associated with the p-wave nature of pion production, the data are insufficient to establish unambiguously the dependence on Q. The angular distributions show the presence of higher partial waves which seem to be anomalously large at small Q. The dispersion relation method to determine scattering lengths is extended to encompass cases where, as for the pp -> pi(+) pn reaction, there is a bound state and, in a test example, it is shown that the values deduced for the low-energy neutron-proton scattering parameters are significantly influenced by the pion p-wave behavior.
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| 17. |
- Fäldt, Göran, et al.
(författare)
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Pion Compton scattering and bremsstrahlung
- 2008
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Ingår i: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 78:1, s. 014606-
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Tidskriftsartikel (refereegranskat)abstract
- The pion polarizability functions are structure functions of pion Compton scattering. They can be assessed in high-energy pion-nucleus bremsstrahlung reactions, pi(-)+A -> ;pi(-)+gamma+A. We present numerical expectations for pion-nucleus bremsstrahlung cross sections in the Coulomb region, i.e., the small-angle region where the nuclear scattering is dominated by the Coulomb interaction. We investigate the prospects of measuring the polarizability functions for pion-Compton center-of-momentum energies from threshold up to 1 GeV. A meson-exchange model is used for the pion Compton amplitude.
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| 18. |
- Fäldt, Göran
(författare)
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Pion polarizabilities and bremsstrahlung
- 2007
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Ingår i: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 76:1, s. 014608-
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Tidskriftsartikel (refereegranskat)abstract
- A model for high-energy, small-angle pion-nucleus bremsstrahlung, π-+A→π-+γ+A, is developed within the Glauber diffraction theory. Special attention is focused on the possibility of measuring the pion polarizability in such reactions. That is the case under the Coulomb peak, provided the bremsstrahlung photon carries practically all the energy of the incident pion. Only radiation from external legs is considered.
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| 19. |
- Fäldt, Göran
(författare)
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Polarization observables in the e+e- ->(Lambda)over-bar Lambda reaction
- 2016
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Ingår i: European Physical Journal A. - : Springer Science and Business Media LLC. - 1434-6001 .- 1434-601X. ; 52:5
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Tidskriftsartikel (refereegranskat)abstract
- Cross-section, vector-polarization, and tensor-polarization distributions are calculated for the reactions e(+)e(-) -> (p) over barp and e(+)e(-) ->(Lambda) over bar Lambda . Each reaction requires six characteristic functions that are bilinear in the, possibly complex, electromagnetic Form factors, denoted G(E)(P-2) and G(M) (P-2), of p and A. For the hyperon reaction also the joint-decay distributions of A and A are calculated. Their knowledge allows a complete determination of the hyperon electromagnetic form factors, without measuring hyperon spins. We explain how this is done in practice. For some tensor-polarization components our results are in conflict with previously repeatedly published distributions.
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| 20. |
- Fäldt, Göran
(författare)
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Production and sequential decay of charmed hyperons
- 2018
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Ingår i: Physical Review D. - 2470-0010 .- 2470-0029. ; 97:5
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Tidskriftsartikel (refereegranskat)abstract
- We investigate production and decay of the Lambda(+)(c) thornc hyperon. The production considered is through the e(+)e(-) annihilation channel, e(+)e(-) -> Lambda(+)(c)(Lambda) over bar (-)(c), with summation over the (Lambda) over bar (-)(c) antihyperon spin directions. It is in this situation that the Lambda(+)(c) decay chain is identified. Two kinds of sequential decays are studied. The first one is the doubly weak decay B-1 -> B2M2, followed by B-2 -> B3M3. The other one is the mixed weak-electromagnetic decay B-1 -> B2M2, followed by B-2 -> B-3 gamma. In both schemes B denotes baryons and M mesons. We should also mention that the initial state of the Lambda(+)(c) thornc hyperon is polarized.
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| 21. |
- Fäldt, Göran
(författare)
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Remark on the Primakoff effect
- 2010
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Ingår i: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 82:3, s. 037603-
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Tidskriftsartikel (refereegranskat)abstract
- The coherent-nuclear reaction a + A -> a(star) + A is in the small-angle region dominated by the one-photon-exchange mechanism, often referred to as the Primakoff effect. In this region information about the electromagnetic decay a(star) -> a + gamma can be obtained. Well-known examples are the two-photon decays of the p and eta mesons. Also, decays of charged hadrons can be studied. For charged hadrons the one-photon-exchange amplitude comes with a Coulomb-phase factor and a Coulomb-form factor, which depend on the ratio between transverse-and longitudinal-momentum transfers, the latter being fixed. At the peak of the cross-section distribution, where the two momentum transfers are equal, the form factor could cut down the cross-section value by as much as 40%. Consequently, a determination of a radiative-decay rate that relies on the peak value becomes sensitive to a proper treatment of the Coulomb-form factor.
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| 22. |
- Fäldt, Göran
(författare)
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Remarks on the analysis of the reaction e(+)e(-) -> Sigma(0)(Sigma)over-bar(0)
- 2021
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Ingår i: Physical Review D. - : American Physical Society. - 2470-0010 .- 2470-0029. ; 103:3
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Tidskriftsartikel (refereegranskat)abstract
- We investigate roads for evaluating model-independent cross-section-distribution functions for the sequential-hyperon decay Sigma(0) -> Lambda gamma; Lambda -> p pi(-) and its corresponding antihyperon decay. The Sigma(0) and (Sigma) over bar (0) hyperons are produced in the reaction e(+)e(-) -> J/psi -> (Sigma) over bar (0)Sigma(0). Cross-section-distribution functions are calculated using the folding technique, but a comparison with results using the helicity technique is also made.
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| 23. |
- Fäldt, Göran, et al.
(författare)
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Sequential hyperon decays in the reaction e(+)e(-) -> Sigma(0)(Sigma)over-bar(0)
- 2020
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Ingår i: Physical Review D. - : AMER PHYSICAL SOC. - 2470-0010 .- 2470-0029. ; 101:3
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Tidskriftsartikel (refereegranskat)abstract
- We report on a study of the sequential hyperon decay Sigma(0) -> Lambda gamma; Lambda -> p pi(-) and its corresponding antihyperon decay. We derive a multidimensional and model-independent formalism for the case when the hyperons are produced in the reaction e(+)e(-) -> Sigma(0)(Sigma) over bar (0). Cross-section distributions are calculated using the folding technique. We also study sequential decays of single-tagged hyperons.
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| 24. |
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| 25. |
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| 26. |
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| 27. |
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| 28. |
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| 29. |
- Fäldt, Göran
(författare)
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Two-photon fusion in high-energy electron-nucleus scattering
- 2011
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Ingår i: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 83:4, s. 044606-
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Tidskriftsartikel (refereegranskat)abstract
- Experimental studies of meson production through two-photon fusion in inelastic electron-nucleus scattering are now under way. A high-energy photon radiated by the incident electron is fused with a soft photon radiated by the nucleus to create the meson. The process takes place in the small-angle Coulomb region of nuclear scattering. We expound the theory for this production process as well as its interference with coherent-radiative-meson production. In particular, we investigate the distortion of the electron wave function due to multiple-Coulomb scattering.
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| 30. |
- Fäldt, Göran, et al.
(författare)
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Two-pion production in deuteron-deuteron collisions at low energies
- 2006
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Ingår i: European Physical Journal A. - : Springer Science and Business Media LLC. - 1434-6001 .- 1434-601X. ; 28:2, s. 245-249
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Tidskriftsartikel (refereegranskat)abstract
- The cross section for the dd->4Hepipi reaction is estimated near threshold in a two-step model where a pion created in the first step produces a second pion in a subsequent interaction.
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| 31. |
- Fäldt, Jenny, 1971, et al.
(författare)
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Reduced exercise endurance in interleukin-6-deficient mice
- 2004
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Ingår i: Endocrinology. - 0013-7227. ; 145:6, s. 2680-6
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Tidskriftsartikel (refereegranskat)abstract
- IL-6 is produced and released in large amounts from skeletal muscle during prolonged exercise in both mice and humans, but there are few data indicating the biological significance of this. IL-6 exerts metabolic effects such as stimulating energy expenditure and reducing body fat mass. We have now investigated the effects of IL-6 deficiency on exercise endurance and energy expenditure in preobese and obese IL-6-deficient (IL-6(-/-)) mice. Four-month-old preobese and 7-month-old obese IL-6(-/-) male mice backcrossed to C57BL/6 and their littermate controls were exercised on a treadmill, and energy expenditure was measured as oxygen consumption with the use of indirect calorimetry. The preobese IL-6(-/-) mice were significantly leaner than the control mice, whereas the older IL-6(-/-) mice, as expected, had developed obesity. Resting young, but not older, IL-6(-/-) mice had an elevated respiratory exchange ratio (RER), indicating that they oxidize carbohydrates rather than fat for energy utilization. During exercise, the young and older IL-6(-/-) mice had a reduced endurance and a progressive decrease in oxygen consumption compared with control mice. There was no difference in RER in young IL-6(-/-) mice, whereas RER was enhanced in older IL-6(-/-), mice during exercise. In summary, IL-6(-/-) mice have reduced endurance and energy expenditure during exercise, suggesting that IL-6 is necessary for normal exercise capacity.
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| 32. |
- Gislén, Lars, et al.
(författare)
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Fragmentation of relativistic nuclei in the α-particle model
- 1975
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Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474. ; 254, s. 341-348
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Tidskriftsartikel (refereegranskat)abstract
- We investigate reactions between high-energy oxygen and carbon nuclei and various nuclear targets. The beam nucleus is described by an α-particle model and the reaction products are classified into groups corresponding to inelastic collisions of one, two, three and four alpha particles. Excellent agreement with experiment is obtained.
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| 33. |
- Nyström, Henrik, 1977, et al.
(författare)
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Platelet-derived growth factor B retention is essential for development of normal structure and function of conduit vessels and capillaries
- 2006
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Ingår i: Cardiovasc Res. - : Oxford University Press (OUP). - 0008-6363. ; 71:3, s. 557-65
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Extracellular retention of PDGF-B has been proposed to play an important role in PDGF-B signalling. We used the PDGF-B retention motif knockout mouse (RetKO) to study the effects of retention motif deletion on development of micro- and macrovascular structure and function. METHODS: Passive and active properties of conduit vessels were studied using myograph techniques and histological examination. Capillary structure and function was studied using measurements of capillary density in skeletal muscle and by assessing aerobic physical performance in a treadmill setup. Cardiac function was assessed using echocardiography. RESULTS: Myograph experiments revealed an increased diameter and stiffness of the aorta in RetKO. Histological examination showed increased media collagen content and a decreased number of aortic wall layers, however with a similar number of vascular smooth muscle cells. This outward eutrophic remodelling of the aorta was accompanied by endothelial dysfunction. RetKO showed decreased capillary density in skeletal muscle and signs of a defective delivery of capillary oxygen to skeletal muscle, as shown by a decreased physical performance. In RetKO mice, echocardiography revealed an adaptive eccentric cardiac hypertrophy. CONCLUSION: We conclude that retention of PDGF-B during development is essential for a normal conduit vessel function in the adult mouse. Furthermore, PDGF-B retention is also necessary for the development of an adequate capillary density, and thereby for a normal oxygen delivery to skeletal muscle. The lack of primary effects on cardiac function supports the redundant role of PDGF-B in cardiac development.
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| 34. |
- Perotti, Elisabetta, et al.
(författare)
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Polarization observables in e(+) e(-) annihilation to a baryon-antibaryon pair
- 2019
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Ingår i: Physical Review D. - 2470-0010 .- 2470-0029. ; 99:5
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Tidskriftsartikel (refereegranskat)abstract
- Using the helicity formalism of Jacob and Wick, we derive spin density matrices of baryon antibaryon pairs produced in e(+)e(-) annihilation. We consider the production of pairs with spins 1/2 + (1/2) over bar, 1/2 + (3/2) over bar (+c.c.) and 3/2 + (3/2) over bar. We provide modular expressions to include chains of weak hadronic two-body decays of the produced hyperons. The expressions are suitable for the analysis of high statistics data from J/psi and psi(2S) ecays at e(+) e(-) colliders, by fits to the fully differential angular distributions of the measured particles. We illustrate the method by examples, such as the inclusive measurement of the e(+) e(-) -> psi(2S) -> Omega(-)(Omega) over bar (+) process where one decay chain Omega(-) -> AK(-) followed by A -> p pi(-) is considered. Finally, we show that the inclusive angular distributions can be used to test spin assignment of the produced baryons.
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| 35. |
- Petrén, Henrik, et al.
(författare)
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eta-meson production in proton-proton collisions at excess energies of 40 and 72 MeV
- 2010
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Ingår i: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 82:5, s. 055206-
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Tidskriftsartikel (refereegranskat)abstract
- The production of eta mesons in proton-proton collisions has been studied using the WASA detector at the CELSIUS storage ring at excess energies of Q = 40 MeV and Q = 72 MeV. The eta was detected through its 2 gamma decay in a near-4 pi electromagnetic calorimeter, whereas the protons were measured by a combination of straw chambers and plastic scintillator planes in the forward hemisphere. About 6.9 x 10(4) and 9.3 x 10(4) events were found at Q = 40 MeV and Q = 72 MeV, respectively, with background contributions of less than 5%. A simple parametrization of the production cross section in terms of low partial waves was used to evaluate the acceptance corrections. Strong evidence was found for the influence of higher partial waves. The Dalitz plots show the presence of p waves in both the pp and the eta {pp} systems and the angular distributions of the eta in the center-of-mass frame suggest the influence of d-wave eta mesons.
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| 36. |
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| 37. |
- Stenmark, Mårten, 1976-
(författare)
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Shout at the eta
- 2004
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Quantum chromodynamics has interesting limits both in the low and the high-energy region. In the low energy region one has phenomenology of meson interactions which are still not clearly understood. In the high-energy region one wants to find a new theory which will envelope gravity and the standard model in the quantum framework, possibly via some kind of string theory.In this thesis some aspects are touched upon including both these limits. On the one hand we look at meson scattering close to threshold and try to describe cross sections via phenomenological models such as the two-step model. We then go on and dwell upon noncommutative geometry, a framework which has been successful in describing certain aspects of the theory of strings.The low-energy calculations gave some insight into the need for finding better understanding of the theories of mesons. The work on noncommutative geometry was on the other hand fruitful in gaining understanding of certain connections between different star products and their relations on a local level.
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| 38. |
- Tengblad, Ulla, et al.
(författare)
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Theoretical description of the pd=>pdeta reaction near threshold
- 2005
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Ingår i: The European Physical Journal A. ; 25, s. 267-273
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Tidskriftsartikel (refereegranskat)abstract
- Three different driving terms for the reaction pd=>pdeta at low energy are evaluated. Near threshold a two-step process dominates whereas impulse diagram contribution is negligible. At energies high enough for eta production in free nucleon-nucleon collisions the pick-up contributions turns out to be suppressed.
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| 39. |
- Wernstedt, Ingrid, 1978, et al.
(författare)
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Reduced stress- and cold-induced increase in energy expenditure in interleukin-6-deficient mice.
- 2006
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Ingår i: American journal of physiology. Regulatory, integrative and comparative physiology. - : American Physiological Society. - 0363-6119 .- 1522-1490. ; 291:3
-
Tidskriftsartikel (refereegranskat)abstract
- Interleukin-6 (IL-6) deficient (-/-) mice develop mature onset obesity. Pharmacological studies have shown that IL-6 has direct lipolytic effects and when administered centrally increases sympathetic outflow. However, the metabolic functions of endogenous IL-6 are not fully elucidated. We aimed to investigate the effect of IL-6 deficiency with respect to cold exposure and cage-switch stress, that is, situations that normally increase sympathetic outflow. Energy metabolism, core temperature, heart rate, and activity were investigated in young preobese IL-6-/- mice by indirect calorimetry together with telemetry. Baseline measurements and the effect of cage-switch stress were investigated at thermoneutrality (30 degrees C) and at room temperature (20 degrees C). The effect of cold exposure was investigated at 4 degrees C. At 30 degrees C, the basal core temperature was 0.6 +/- 0.24 degrees C lower in IL-6-/- compared with wild-type mice, whereas the oxygen consumption did not differ significantly. The respiratory exchange ratio at 20 degrees C was significantly higher and the calculated fat utilization rate was lower in IL-6-/- mice. In response to cage-switch stress, the increase in oxygen consumption at both 30 and 20 degrees C was lower in IL-6-/- than in wild-type mice. The increase in heart rate was lower in IL-6-/- mice at 30 degrees C. At 4 degrees C, both the oxygen consumption and core temperature were lower in IL-6-/- compared with wild-type mice, suggesting a lower cold-induced thermogenesis in IL-6-/- mice. The present results indicate that endogenous IL-6 is of importance for stress- and cold-induced energy expenditure in mice.
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| 40. |
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| 41. |
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