| 1. |
- Aksyutina, Yu, et al.
(författare)
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Lithium isotopes beyond the drip line
- 2008
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Ingår i: Physics Letters B. - : Elsevier BV. - 0370-2693. ; 666:5, s. 430-434
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Tidskriftsartikel (refereegranskat)abstract
- The unbound isotopes 10Li, 12Li and 13Li have been observed after nucleon-knockout reactions at relativistic energies with 11Li and 14Be beams impinging on a liquid hydrogen target. The channels , and were analysed in the ALADIN-LAND setup at GSI. The 10Li data confirm earlier findings, while the 12Li and 13Li nuclei were observed for the first time. The relative-energy spectrum shows that the ground state of 12Li can be described as a virtual s-state with a scattering length of -13.7(1.6) fm. A broad energy spectrum was found for the channel. Based on the assumption that the relative-energy spectrum is dominated by a correlated background presumably stemming from initial correlations in the 14Be ground-state, evidence for a 13Li resonance at 1.47(31) MeV above the threshold with a width around 2 MeV has been found.
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| 2. |
- Güsten, R., et al.
(författare)
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APEX - The Atacama Pathfinder Experiment
- 2006
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Ingår i: Proceedings of SPIE - The International Society for Optical Engineering. - : SPIE. - 0277-786X .- 1996-756X. ; 6267 I
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Konferensbidrag (refereegranskat)abstract
- APEX, the Atacama Pathfinder Experiment, has been successfully commissioned and is in operation now. This novel submillimeter telescope is located at 5107 m altitude on Llano de Chajnantor in the Chilean High Andes, on what is considered one of the world's outstanding sites for submillimeter astronomy. The primary reflector with 12 m diameter has been carefully adjusted by means of holography. Its surface smoothness of 17-18 μm makes APEX suitable for observations up to 200 μm, through all atmospheric submm windows accessible from the ground.
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| 3. |
- Maierbeck, P., et al.
(författare)
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Probing the single particle structure around Ca-54 with one-neutron knock-out
- 2008
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Ingår i: AIP Conference Proceedings. - 1551-7616 .- 0094-243X. ; 1012, s. 89-93
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Konferensbidrag (refereegranskat)abstract
- The nuclei Ca-47 and Ti-55 were populated in one-neutron knock-out reactions at relativistic energies. Momentum distributions of the residual nuclei as well as gamma-ray spectra were measured at the GSI fragment separator (FRS). Preliminary results of the ongoing analysis including cross sections and spin/parity assignments are presented.
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| 4. |
- Maierbeck, P., et al.
(författare)
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Structure of 55Ti from relativistic one-neutron knockout
- 2009
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Ingår i: Physics Letters B. - : Elsevier BV. - 0370-2693. ; 675:1, s. 22-27
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Tidskriftsartikel (refereegranskat)abstract
- Results are presented from a one-neutron knockout reaction at relativistic energies on 56Ti using the GSI FRS as a two-stage magnetic spectrometer and the Miniball array for gamma-ray detection. Inclusive and exclusive longitudinal momentum distributions and cross-sections were measured enabling the determination of the orbital angular momentum of the populated states. First-time observation of the 955(6) keV -hole state in 55Ti is reported. The measured data for the first time proves that the ground state of 55Ti is a 1/2- state, in agreement with shell-model calculations using the GXPF1A interaction that predict a sizable N=34 gap in 54Ca.
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| 5. |
- Aksyutina, Yuliya, 1983, et al.
(författare)
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Properties of the 7He ground state from 8He neutron knockout
- 2009
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Ingår i: Physics Letters B. - : Elsevier BV. - 0370-2693. ; 679:3, s. 191-196
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Tidskriftsartikel (refereegranskat)abstract
- The unbound nucleus 7He, produced in neutron-knockout reactions with a 240 MeV/u 8He beam in a liquid-hydrogen target, has been studied in an experiment at the ALADIN-LAND setup at GSI. From an R-matrix analysis the resonance parameters for 7He as well as the spectroscopic factor for the 6He(0+) + n configuration in its ground-state have been obtained. The spectroscopic factor is 0.61 confirming that 7He is not a pure single-particle state. An analysis of 5He data from neutron-knockout reactions of 6He in a carbon target reveals the presence of an s-wave component at low energies in the α+n relative energy spectrum. A possible low-lying exited state in 7He observed in neutron knockout data from 8He in a carbon target and tentatively interpreted as a Iπ=1/2− state, could not be observed in the present experiment. Possible explanations of the shape difference between the 7He resonance obtained in the two knockout reactions are discussed in terms of target-dependence or different reaction mechanisms at relativistic energies.
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| 6. |
- Hyldegaard, S., et al.
(författare)
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Precise branching ratios to unbound 12C states from 12N and 12B [beta]-decays
- 2009
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Ingår i: Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 678:5, s. 459 - 464
-
Tidskriftsartikel (refereegranskat)abstract
- Two complementary experimental techniques have been used to extract precise branching ratios to unbound states in 12C from 12N and 12B [beta]-decays. In the first the three [alpha]-particles emitted after [beta]-decay are measured in coincidence in separate detectors, while in the second method 12N and 12B are implanted in a detector and the summed energy of the three [alpha]-particles is measured directly. For the narrow states at 7.654 MeV (0+) and 12.71 MeV (1+) the resulting branching ratios are both smaller than previous measurements by a factor of [similar, equals]2. The experimental results are compared to no-core shell model calculations with realistic interactions from chiral perturbation theory, and inclusion of three-nucleon forces is found to give improved agreement.
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| 7. |
- Jeppesen, H. B., et al.
(författare)
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Investigation of the Li-9+H-2 -> Li-8+t reaction at REX-ISOLDE
- 2006
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Ingår i: Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 635, s. 17-17
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Tidskriftsartikel (refereegranskat)abstract
- The one-neutron transfer reaction Li-9 + H-2 -> Li-8 + t has been investigated in an inverse kinematics experiment by bombarding a deuterated polypropylene target with a 2.36 MeV/u Li-9 beam from the post-accelerator REX-ISOLDE at CERN. Excitation energies in Li-8 as well as angular distributions of the tritons were obtained and spectroscopic factors deduced. (c) 2006 Elsevier B.V. All rights reserved.
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| 8. |
- Jeppesen, H. B., et al.
(författare)
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Low energy reactions with radioactive ions at REX-ISOLDE - the Li-9+H-2 case
- 2005
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Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474. ; 748, s. 374-374
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Tidskriftsartikel (refereegranskat)abstract
- At the newly constructed postaccelerator REX-ISOLDE (Radioactive beam Experiment at ISOLDE) we have investigated reactions induced by a Li-9 beam incident on a deuterium target at an energy of 2.36 MeV/u. Most reaction channels were recorded. From one-neutron transfer the differential cross-section for the low lying Li-10 spectrum is found. The results from the other channels demonstrate the great applicability and many possibilities that REX-ISOLDE opens up.
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| 9. |
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| 10. |
- Fynbo, H. O. U., et al.
(författare)
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The β-decay approach for studying 12C
- 2008
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Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 111:1
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Tidskriftsartikel (refereegranskat)abstract
- The β-decays of the mirror nuclei 12B and 12N both populate states in 12C and they are therefore a precious source of information about this nucleus. Due to the selection rules of β-decay only 0+, 1+ and 2+ states are populated. This allows a very clean study of unbound states just above the 3α-threshold with those spin and parities. This probe has been applied in two experiments using two complementary experimental techniques: in the first the three α-particles emitted after β-decay are measured in coincidence in separate detectors using the ISOL method, while in the second method 12B and 12N are implanted in a detector and the summed energy of the three α-particles is measured directly. Preliminary results from the two approaches are presented. © 2008 IOP Publishing Ltd.
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| 11. |
- Hyldegaard, S., et al.
(författare)
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STUDIES OF C-12 USING beta-DECAYS
- 2008
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Ingår i: International Journal of Modern Physics E. - 0218-3013. ; 17:10, s. 2182-2187
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Konferensbidrag (refereegranskat)abstract
- The nuclear structure of states in C-12 have been a subject of interest for both theory and experiment since the early days of nuclear physics. Many open questions remain, especially concerning the existence and properties of 0(+) and 2(+) states in the triple alpha continuum. A series of experiments have been performed using beta-decay of N-12 and B-12 to probe these states. The latest experiment was performed at KVI using an implantation method, measuring the sum energy of the three alpha-particles directly. Preliminary results from this experiment will be presented.
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| 12. |
- Chulkov, L. V., et al.
(författare)
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Three-body correlations in electromagnetic dissociation of Borromean nuclei: The He-6 case
- 2005
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Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474. ; 759:1-2, s. 23-42
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Tidskriftsartikel (refereegranskat)abstract
- Dissociation of He-6 on a lead target has been studied at 240 MeV/u. The four-momenta of the two neutrons in coincidence with alpha-particles have been measured and used to reconstruct the three-body energy and angular correlations in the final state. For the first time, three-body correlations were included in the analysis of the He-6 dissociation data, and compared with calculations assuming a dipole mode for the electromagnetic dissociation. In addition, the experimental data have been analyzed using a series expansion of the final transition amplitude into hyperspherical functions, showing the importance of both nn and alpha n final-state interactions. It is shown that the dissociation process is governed by a transition of one neutron from the p-shell in the 6He ground state to the s-shell in the continuum further indicating that the role of the transition through an intermediate He-5(3/2(-)) state is more important than expected. (c) 2005 Elsevier B.V. All rights reserved.
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| 13. |
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| 14. |
- Fynbo, H. O. U., et al.
(författare)
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Revised rates for the stellar triple-alpha process from measurement of C-12 nuclear resonances
- 2005
-
Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687 .- 1476-4679. ; 433:7022, s. 136-139
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Tidskriftsartikel (refereegranskat)abstract
- In the centres of stars where the temperature is high enough, three alpha-particles (helium nuclei) are able to combine to form C-12 because of a resonant reaction leading to a nuclear excited state(1). (Stars with masses greater than similar to0.5 times that of the Sun will at some point in their lives have a central temperature high enough for this reaction to proceed.) Although the reaction rate is of critical significance for determining elemental abundances in the Universe(1), and for determining the size of the iron core of a star just before it goes supernova(2), it has hitherto been insufficiently determined(2). Here we report a measurement of the inverse process, where a C-12 nucleus decays to three alpha-particles. We find a dominant resonance at an energy of similar to11 MeV, but do not confirm the presence of a resonance at 9.1 MeV (ref. 3). We show that interference between two resonances has important effects on our measured spectrum. Using these data, we calculate the triple-a rate for temperatures from 10(7) K to 10(10) K and find significant deviations from the standard rates(3). Our rate below similar to5 x 10(7) K is higher than the previous standard, implying that the critical amounts of carbon that catalysed hydrogen burning in the first stars are produced twice as fast as previously believed(4). At temperatures above 10(9) K, our rate is much less, which modifies predicted nucleosynthesis in supernovae(5,6).
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| 15. |
- Hyldegaard, S., et al.
(författare)
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Branching ratios in the beta decays of N-12 and B-12
- 2009
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Ingår i: Physical Review C - Nuclear Physics. - 2469-9985 .- 2469-9993. ; 80:4
-
Tidskriftsartikel (refereegranskat)abstract
- Absolute branching ratios to unbound states in C-12 populated in the beta decays of N-12 and B-12 are reported. Clean sources of N-12 and B-12 were obtained using the isotope separation on-line (ISOL) method. The relative branching ratios to the different populated states were extracted using single-alpha as well as complete kinematics triple-alpha spectra. These two largely independent methods give consistent results. Absolute normalization is achieved via the precisely known absolute branching ratio to the bound 4.44 MeV state in C-12. The extracted branching ratios to the unbound states are a factor of three more precise than previous measurements. Branching ratios in the decay of Na-20 are also extracted and used to check the results.
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| 16. |
- Petts, A., et al.
(författare)
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Lifetime measurements and coulomb excitation of light Hg nuclei
- 2009
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Ingår i: Capture Gamma-Ray Spectroscopy and Related Topics. - : American Institute of Physics (AIP). - 9780735406230 ; , s. 414-418
-
Konferensbidrag (refereegranskat)abstract
- Two complementary experimental programs have taken place to investigate the origin and evolution of shape coexistence in the light mercury region. Recoil Distance Doppler-shift measurements were performed at the University of Jyväskylä utilizing the Köln plunger device in conjunction with the JUROGAM + RITU + GREAT setup. In addition, Coulomb excitation measurements of 184,186,188Hg were performed at REX-ISOLDE using the MINIBALL Ge-detector array. The results of the lifetime measurements of the yrast states up to Iπ = 10+ in 182Hg are reported. Preliminary analysis of the Coulomb excitation data is also discussed.
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| 17. |
- Wadsworth, R., et al.
(författare)
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THE NORTHWEST FRONTIER : SPECTROSCOPY OF N similar to Z NUCLEI BELOW MASS 100
- 2009
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Ingår i: Acta Physica Polonica B. - 0587-4254 .- 1509-5770. ; 40:3, s. 611-620
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Tidskriftsartikel (refereegranskat)abstract
- The spectroscopy and structure of excited states of N similar to Z nuclei in the mass 70-100 region has been investigated using two techniques. In the A similar to 70-80 region fusion evaporation reactions coupled with the recoil-beta-tagging method have been employed at Jyvaskyla to study low-lying states in odd-odd N = Z nuclei. Results from these and other data for known odd-odd nuclei above mass 60 will be discussed. In the heavier mass 90 region a fragmentation experiment has been performed using the RIS-ING/FRS setup at GSI. This experiment was primarily aimed at searching for spin gap isomers in nuclei around A similar to 96. The objectives of the latter experiment will be discussed.
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| 18. |
- Alcorta, M., et al.
(författare)
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Nuclear Structure of C-12 from Break-up Studies in Complete Kinematics
- 2009
-
Ingår i: AIP Conference Proceedings. - : AIP. - 1551-7616 .- 0094-243X. - 9780735407022 ; 1165, s. 27-30 461
-
Konferensbidrag (refereegranskat)abstract
- A complete kinematics study of the B-10(He-3,p alpha alpha alpha) and B-11(He-3,d alpha alpha alpha) reactions has been performed to study the multi-particle break-up of C-12 resonances above the triple-alpha threshold. Four-particle coincidence detection gives us complete information on the direction and energy of the individual alpha particles from the decay of C-12, allowing us to extract new information on the structure of C-12 which we shall present in this contribution. We have observed gamma de-excitation of the T=1 15.11 MeV resonance using charged particle detectors, and have constructed Dalitz plots of the individual resonances in C-12 using the complete kinematics information of the alpha particles which come from their break-up.
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| 19. |
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| 20. |
- Diget, C. A., et al.
(författare)
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Breakup channels for C-12 triple-alpha continuum states
- 2009
-
Ingår i: Physical Review C - Nuclear Physics. - 2469-9985 .- 2469-9993. ; 80:3
-
Tidskriftsartikel (refereegranskat)abstract
- The triple-alpha-particle breakup of states in the triple-alpha continuum of C-12 has been investigated by way of coincident detection of all three alpha particles of the breakup. The states have been fed in the beta decay of N-12 and B-12, and the alpha particles measured using a setup that covers all of the triple-alpha phase space. Contributions from the breakup through the Be-8(0(+)) ground state as well as other channels-interpreted as breakup through excited energies in Be-8-have been identified. Spins and parities of C-12 triple-alpha continuum states are deduced from the measured phase-space distributions for breakup through Be-8 above the ground state by comparison to a fully symmetrized sequential R-matrix description of the breakup. At around 10 MeV in C-12, the breakup is found to be dominated by 0(+) strength breaking up through the ghost of the Be-8(0(+)) ground state with L = 0 angular momentum between the first emitted alpha particle and the intermediate Be-8 nucleus. For C-12 energies above the 12.7 MeV 1(+) state, however, L = 2 breakup of a C-12 2(+) state through the Be-8(2(+)) excited state dominates. Furthermore, the possibility of a 2(+) excited state in the 9-12 MeV region of C-12 is investigated.
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| 21. |
- Diget, C. A., et al.
(författare)
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Properties of the C-12 10 MeV state determined through beta-decay
- 2005
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Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474. ; 760:1-2, s. 3-18
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Tidskriftsartikel (refereegranskat)abstract
- The beta-delayed triple-alpha particle decay of B-12 has been measured with a setup that favours coincidence detection. A broad state in C-12, previously reported around 10 MeV, has been seen and its properties determined through R-matrix analysis of the excitation spectrum. The spin and parity are 0(+). Interference between this state and the Hoyle state at 7.654 MeV has a marked influence on the spectrum. The coupling between the two states makes it difficult to determine the resonance energy. (c) 2005 Elsevier B.V. All rights reserved.
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| 22. |
- Geijer, Fredrik, et al.
(författare)
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Minimizing Contrast Medium Doses to Diagnose Pulmonary Embolism with 80-kVp Multidetector Computed Tomography in Azotemic Patients.
- 2009
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Ingår i: Acta radiologica (Stockholm, Sweden : 1987). - : SAGE Publications. - 1600-0455 .- 0284-1851. ; 50, s. 181-193
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Tidskriftsartikel (refereegranskat)abstract
- Background: In diagnosing acute pulmonary embolism (PE) in azotemic patients, scintigraphy and magnetic resonance imaging are frequently inconclusive or not available in many hospitals. Computed tomography is readily available, but relatively high doses (30-50 g I) of potentially nephrotoxic iodine contrast media (CM) are used. Purpose: To report on the diagnostic quality and possible contrast-induced nephropathy (CIN) after substantially reduced CM doses to diagnose PE in azotemic patients using 80-peak kilovoltage (kVp) 16-row multidetector computed tomography (MDCT) combined with CM doses tailored to body weight, fixed injection duration adapted to scan time, automatic bolus tracking, and saline chaser. Material and Methods: Patients with estimated glomerular filtration rate (eGFR) <50 ml/min were scheduled to undergo 80-kVp MDCT using 200 mg I/kg, and those with eGFR >/=50 ml/min, 120-kVp MDCT with 320 mg I/kg. Both protocols used an 80-kg maximum dose weight and a fixed 15-s injection time. Pulmonary artery density and contrast-to-noise ratio were measured assuming 70 Hounsfield units (HU) for a fresh clot. CIN was defined as a plasma creatinine rise >44.2 micromol/l from baseline. Results: 89/148 patients (63/68 females) underwent 80-/120-kVp protocols, respectively, with 95% of the examinations being subjectively excellent or adequate. Mean values in the 80-/120-kVp cohorts regarding age were 82/65 years, body weight 66/78 kg, effective mAs 277/117, CM dose 13/23 g I, pulmonary artery density 359/345 HU, image noise (1 standard deviation) 24/21 HU, contrast-to-noise ratio 13/13, and dose-length product 173/258 mGy.cm. Only 1/65 and 2/119 patients in the 80- and 120-kVp cohorts, respectively, with negative CT and no anticoagulation suffered non-fatal thromboembolism during 3-month follow-up. No patient developed CIN. Conclusion: 80-kVp 16-row MDCT with optimization of injection parameters may be performed with preserved diagnostic quality, using markedly reduced CM doses compared with common routine practice, which should be to the benefit of patients at risk of CIN.
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| 23. |
- Grahn, K, et al.
(författare)
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Attitudes about dental care among parents whose children suffer from severe congenital heart disease : a case-control study
- 2006
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Ingår i: International Journal of Paediatric Dentistry. - 0960-7439 .- 1365-263X. ; 16:4, s. 231-238
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: To examine attitudes and experiences of parents whose children have complex congenital heart disease (CHD) with respect to dental health information and advice, dental care, and service and to compare the results with data from an age- and gender-matched control group without any medical problems. SETTING: Faculty of Medicine (Paediatric Cardiology and Paediatric Dentistry), Umea University, Umea, Sweden. SAMPLE AND METHOD: Each group comprised parents of 33 children; the children's mean age was 9.4 years. All the cases and the controls resided in the county of Vasterbotten, northern Sweden. Data were collected with a questionnaire with 20 joint questions to both groups and four additional questions to the CHD group. RESULTS: Of the 20 joint questions, significant differences were displayed in the following areas: the professional group that provided the parents with dental health information and advice (P < 0.01), attitudes to reception at the dental clinic, and experience of sedation before operative dental treatment (P < 0.05). Parents to 11 children with CHD who were patients at a specialist clinic for paediatric dentistry scored the reception at the dental clinic as excellent in nine cases and satisfactory in two, compared to excellent (3), satisfactory (11), decent (4), and poor (4) among those who were patients in general dental practice (P < 0.01). No statistically significant differences in educational level or in parental experience of dental health were noted between the two groups (P > 0.05). CONCLUSION: Children with CHD in northern Sweden mainly receive their dental health information from a physician or a dentist, and healthy children mainly receive information from a dental hygienist indicating that children with CHD are given priority in the dental care system. Parental attitudes to reception in the dental service differed, and parents of healthy children scored the reception at the dental clinic better than parents of children with CHD. It is suggested that children with severe CHD should receive dental care in clinics for paediatric dentistry, particularly at early ages.
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| 24. |
- Grahn, T., et al.
(författare)
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Collectivity and configuration mixing in Pb186,188 and Po194
- 2006
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Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 97:6
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Tidskriftsartikel (refereegranskat)abstract
- Lifetimes of prolate intruder states in Pb186 and oblate intruder states in Po194 have been determined by employing, for the first time, the recoil-decay tagging technique in recoil distance Doppler-shift lifetime measurements. In addition, lifetime measurements of prolate states in Pb188 up to the 8+ state were carried out using the recoil-gating method. The B(E2) values have been deduced from which deformation parameters |β2|=0.29(5) and |β2|=0.17(3) for the prolate and the oblate bands, respectively, have been extracted. The results also shed new light on the mixing between different shapes.
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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. |
- Jeppesen, H. B., et al.
(författare)
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Study of Li-10 via the Li-9(H-2, p) reaction at REX-ISOLDE
- 2006
-
Ingår i: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 642:5-6, s. 449-454
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Tidskriftsartikel (refereegranskat)abstract
- The Click to view the MathML source reaction has been investigated at 2.36 MeV/u at the REX-ISOLDE facility. In this Letter we focus on the Click to view the MathML source channel which potentially holds spectroscopic information on the unbound nucleus 10Li. The experimental excitation energy spectrum and angular distribution are compared with CCBA calculations. These calculations clearly support the existence of a low-lying (s) virtual state, with a (negative) scattering length of the order asnot, vert, similar1324 fm and a p1/2 resonance with an energy of Ersimilar, equals0.38 MeV and a width of Γsimilar, equals0.2 MeV.
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| 30. |
- Ketelhut, S., et al.
(författare)
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gamma-Ray Spectroscopy at the Limits : First Observation of Rotational Bands in Lr-255
- 2009
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Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 102:21, s. 212501-
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Tidskriftsartikel (refereegranskat)abstract
- The rotational band structure of Lr-255 has been investigated using advanced in-beam gamma-ray spectroscopic techniques. To date, Lr-255 is the heaviest nucleus to be studied in this manner. One rotational band has been unambiguously observed and strong evidence for a second rotational structure was found. The structures are tentatively assigned to be based on the 1/2(-)[521] and 7/2(-)[514] Nilsson states, consistent with assignments from recently obtained alpha decay data. The experimental rotational band dynamic moment of inertia is used to test self-consistent mean-field calculations using the Skyrme SLy4 interaction and a density-dependent pairing force.
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| 31. |
- Kirsebom, O. S., et al.
(författare)
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Observation of gamma-delayed 3 alpha breakup of the 15.11 and 12.71 MeV states in C-12
- 2009
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Ingår i: Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 680:1, s. 44-49
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Tidskriftsartikel (refereegranskat)abstract
- The reactions B-10(He-3, p alpha alpha alpha) at 4.9 MeV and B-11(He-3, d alpha alpha alpha) at 8.5 MeV have been used to investigate the gamma decay of states in C-12. By measuring the four-body final state in complete kinematics we are able to detect gamma transitions indirectly. We find gamma transitions from the 15.11 MeV state in C-12 to the 12.71, 11.83, 10.3 and 7.65 MeV states followed by their breakup into three alpha particles. The relative gamma-ray branching ratios obtained are (1.2 +/- 0.3), (0.32 +/- 0.12), (1.4 +/- 0.2) and (4.4 +/- 0.8)%, respectively, with the remaining (92.7 +/- 1.0)% of the gamma decays going to the bound states. We obtain Gamma(alpha)/Gamma = (2.8 +/- 1.2)% for the isospinforbidden alpha decay of the 15.11 MeV state. From the 12.71 MeV state we find gamma transitions to the 10.3 and 7.65 MeV states. The relative gamma-ray branching ratios are (0.9(-0.5)(+0.6)) and (2.6(-1.2)(+1.6))%, respectively, with the remaining (96.6(-1.3)(+1.7))% of the gamma decays going to the bound states. Finally. we discuss the relation between the beta decay of N-12 and B-12 to states in C-12 and the gamma decay of the 15.11 MeV analog in C-12 to the same states. (C) 2009 Elsevier B.V. All rights reserved.
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| 32. |
- Knudsen, H. H., et al.
(författare)
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Beta-decay of 13O
- 2005
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Ingår i: Physical Review C - Nuclear Physics. - 2469-9985 .- 2469-9993. ; 72:4, s. 044312-
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Tidskriftsartikel (refereegranskat)abstract
- The beta decay of O-13 has been studied at the IGISOL facility of the Jyvaskyla accelerator centre (Finland). By developing a low-energy isotope-separated beam of O-13 and using a modern segmented charged-particle detector array an improved measurement of the delayed proton spectrum was possible. Protons with energy up to more than 12 MeV are measured and the corresponding log(ft) values extracted. A revised decay scheme is constructed. The connection to molecular states and the shell model is discussed.
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| 33. |
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| 34. |
- Lindahl, E, et al.
(författare)
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Cellular internalization of proinsulin C-peptide
- 2007
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Ingår i: Cellular and molecular life sciences : CMLS. - : Springer Science and Business Media LLC. - 1420-682X .- 1420-9071. ; 64:4, s. 479-486
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Tidskriftsartikel (refereegranskat)
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| 35. |
- Madurga, M., et al.
(författare)
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beta-delayed particle studies of the halo nucleus Li-11 and its core Li-9
- 2008
-
Ingår i: AIP Conference Proceedings. - 1551-7616 .- 0094-243X. ; 1012, s. 193-197 453
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Konferensbidrag (refereegranskat)abstract
- The beta-decay of Li-11 and its core Li-9 has been revisited with the aim to disentangle the very complex decays from unbound states in the daughters. The decay channels for the states fed by beta-decay in Be-9 are established including the 2.43 MeV state for which the analysis of alpha alpha and n alpha spectra seem to favour direct break-up of the level. For the decay of Li-11 the beta-delayed charged particle spectrum can be explained by the contribution of the 10.6 and 18.2 MeV states. The alpha alpha correlations indicates that decay through resonant He-isotopes are more likely than phase space distributed 5-body break-up.
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| 36. |
- Madurga, M., et al.
(författare)
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Evidence of a new state in Be-11 observed in the Li-11 beta-decay
- 2009
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Ingår i: Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 677:5, s. 255-259
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Tidskriftsartikel (refereegranskat)abstract
- Coincidences between charged particles emitted in the beta-decay of Li-11 were observed using highly segmented detectors. The breakup channels involving three particles were Studied in full kinematics allowing for the reconstruction of the excitation energy of the Be-11 states participating in the decay. In particular, the contribution of a previously unobserved state at 16.3 MeV in Be-11 has been identified selecting the alpha + He-7 -> alpha + He-6 + n channel. The angular correlations between the alpha particle and the center of mass of the He-6 + n system favors spin and parity assignment of 3/2(-) for this state as well as for the previously known state at 18 MeV. (C) 2009 Elsevier B.V. All rights reserved.
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| 37. |
- Madurga, M., et al.
(författare)
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Kinematic identification of the t branch in the decay of 11Li
- 2009
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Ingår i: European Physical Journal A. - : Springer Science and Business Media LLC. - 1434-601X .- 1434-6001. ; 42:3, s. 415-419
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Tidskriftsartikel (refereegranskat)abstract
- The -delayed 8 Li + t branch of the 11Li decay was identified via kinematical analysis of the charged particles observed in coincidence. The back-to-back events observed in a narrow angular acceptance were compared to a Monte Carlo simulation. The 8 Li + t sum energy spectrum was fitted assuming that the decay occurs through an intermediate state in 11Be . The resulting energy centroid and full-width half maximum for the intermediate state are 18.35(30)MeV and 1.5(4)MeV, respectively. The -delayed 8 Li + t branching ratio obtained from the coincidence spectrum, BR t = 0.93(8)×10-4 , is in agreement with previous measurements but more precise.
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| 38. |
- Madurga, M., et al.
(författare)
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Multiple particle break-up study of low excited states in Be-9: The ghost peak in the Be-8 excitation energy spectrum visited
- 2007
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Ingår i: European Physical Journal: Special Topics. - : Springer Science and Business Media LLC. - 1951-6401 .- 1951-6355. ; 150:1, s. 137-138
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this work is to find out the origin of the anomalous resonance in Be-8 seen in the reactions through excited states in Be-9. We have populated the Be-9 excited states by beta-decay of Li-9. Energy and direction of the two alpha particles has been detected and the neutron spectra reconstructed. In our work we identified the "anomalous resonance" in Be-8 observed in several reaction studies as coming from the decay of the 2.43 and 2.78 MeV states in Be-9. This anomalous resonance appears when the two detected alpha particles are assumed to form a resonance in Be-8. We argued that the main decaying channels for these two levels in Be-9 do not involve Be-8.
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| 39. |
- Madurga, M., et al.
(författare)
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Study of $[$beta$]$-delayed 3-body and 5-body breakup channels observed in the decay of 11Li
- 2008
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Ingår i: Nuclear Physics A. - : Elsevier BV. ; 810, s. 1-12
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Tidskriftsartikel (refereegranskat)abstract
- The [beta]-delayed charged particle emission from 11Li has been studied with emphasis on the three-body n[alpha]6He and five-body 2[alpha]3n channels from the 10.59 and 18.15 MeV states in 11Be. Monte Carlo simulations using an R-matrix formalism lead to the conclusion that the AHe resonance states play a significant role in the break-up of these states. The results exclude an earlier assumption of a phase-space description of the break-up process of the 18.15 MeV state. Evidence for extra sequential decay paths is found for both states.
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| 40. |
- Madurga, M., et al.
(författare)
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Study of β-delayed charged particle emission of 11Li: Evidence of new decay channels
- 2008
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Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 111:1
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Tidskriftsartikel (refereegranskat)abstract
- The break-up of the 18.2 MeV state in 11Be was studied in a 11Li β-decay experiment. We report here on the study of the dominating breakup channels involving na6He or 3n2α in the final state, with special emphasis dedicated in this contribution to the three-particle channel. The two emitted charged particles were detected in coincidence using a highly segmented experimental set-up. The observed experimental energy-vs-energy scatter plot indicates a sequential breakup where nuclei of mass 4, alpha particles, and mass 7, 7He, are involved. A Monte-Carlo simulation of the sequential channel, 11Be* → α + 7He → nα6He was performed and compared to the experimental data and to a simulation of the direct break-up of the 18.2 MeV state nα6He by phase space energy distribution. The energy-versus-energy plot are explained by the sequential simulation but not by the phase space simulation.
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| 41. |
- Nilsson, J, et al.
(författare)
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Variation in the content of glucosinolates, hydroxycinnamic acids, carotenoids, total antioxidant capacity and low-molecular-weight carbohydrates in Brassica vegetables
- 2006
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Ingår i: Journal of the Science of Food and Agriculture. - : Wiley. - 1097-0010 .- 0022-5142. ; 86:4, s. 528-538
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Tidskriftsartikel (refereegranskat)abstract
- Bioactive compounds were investigated in genotypes (cauliflower 10, white cabbage 10, curly kale 1) and plant parts of the three crops. The content of most of the major glucosinolates glucobrassicin, sinigrin and glucoiberin differed significantly between cultivars. Samples harvested in 2000 had higher amounts of several glucosinolates than samples from 1999. Within cauliflower the buds of the floret had 1.5 to 2.5-fold higher concentration of glucobrassicin and 4-methoxyglucobrassicin than the stalk. In white cabbage several glucosinolates had their highest content in the outer leaves (up to 2-fold higher). Upper leaves of curly kale contained 5-fold more of total glucosinolates than lower leaves. Chlorogenic acid was the dominating hydroxycinnamate in curly kale, which also contained at least ten times more of carotenoids (mainly lutein) than white cabbage. Total antioxidant capacity (TAC) assayed with the FRAP method was 0.76 (0.06) mu mol/g fw (mean (SD)) in water-soluble and 0.32 (0.04) in water-insoluble extracts of cauliflower which was 62-68% higher than in white cabbage. Curly kale contained 6.4 and 6.1 mu mol/g fw TAC in water-soluble and water-insoluble extracts. TAC did not differ between plant parts. Progoitrin and 4-hydroxyglucobrassicin were correlated to water-soluble TAC in white cabbage, probably reflecting a variation in other compounds. Cauliflower contained less glucose, fructose and sorbitol but more sucrose than white cabbage. Curly kale had lower contents of glucose (similar to 2 times), fructose (similar to 4-S times) and sucrose (20 and 36 times, respectively) than cauliflower and white cabbage, while inositol was only found in curly kale. Storage of white cabbage reduced the amount of sorbitol and sucrose. The study shows that cultivar, plant part and storage affect the content of bioactive compounds in Brassica vegetables. The variation between years, as in cauliflower, is due to environmental factors. Since the cultivar ranking order was rather stable for several components the data could provide a basis for the selection of cultivars optimised for valuable health components for fresh market consumption. (c) 2005 Society of Chemical Industry.
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| 42. |
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| 43. |
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| 44. |
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| 45. |
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| 46. |
- Prezado, Y., et al.
(författare)
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Low-lying resonance states in the Be-9 continuum
- 2005
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Ingår i: Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 618:1-4, s. 43-50
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Tidskriftsartikel (refereegranskat)abstract
- Excited states in Be-9 from 2 to 9 MeV are studied via beta delayed particle emission from Li-9. The broad overlapping particle unbound states are investigated using an extension of an experimental method developed for dealing with three-body decays of broad isolated levels. The results confirm the existence of a broad state at 5 MeV, with a width of 2 MeV. Angular correlations are used for firm spin determinations for this and other levels.
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| 47. |
- Ruck, Christian, et al.
(författare)
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Capsulotomy for Obsessive-Compulsive Disorder : long term follow up of 25 patients
- 2008
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Ingår i: Archives of General Psychiatry. - : American Medical Association (AMA). - 0003-990X .- 1538-3636. ; 65:8, s. 914-922
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Tidskriftsartikel (refereegranskat)abstract
- Abstract Context: Capsulotomy is sometimes used as a treatment of last resort in severe and treatment refractory cases of Obsessive-Compulsive Disorder (OCD). Objective: To evaluate the long-term efficacy and safety of capsulotomy in OCD. Design: Non-controlled long-term follow-up trial (mean 10.9 years after surgery). Setting: University hospital referral center. Patients: 25 consecutive OCD patients having undergone capsulotomy between the years 1988 and 2000. Intervention: Unilateral or bilateral capsulotomy. Lesions were created either by conventional heating or by gamma-radiation (radiosurgery). Main Outcome Measure: Yale-Brown Obsessive-Compulsive Rating Scale (Y-BOCS). Results: Mean Y-BOCS was 34 preoperatively and dropped to 18 at long-term follow-up (p<0.0001). Response (defined as ≥ 35 % reduction at long-term compared to baseline) was seen in 12 patients at long-term. Eight patients were in remission (Y-BOCS < 16) at long-term follow-up. Response rates did not differ between surgical method. A mean weight gain of 6 kg was reported in the first postoperative year. Ten patients were considered to sufferer from significant problems in the area of executive functioning, apathy or disinhibition. Six of these ten patients had either had high doses of radiation or multiple surgical procedures. Our MRI analysis of 11 patients suggests that the OCD symptom reduction may be increased by reducing the lateral extension of the lesions, and a reduction in the medial and posterior extension may limit the risk of side effects, that is, smaller lesions may produce better results. Conclusions: Capsulotomy is effective in reducing OCD symptoms. There is a substantial risk of side effects and the risk may vary between surgical methods. Our findings suggest that smaller lesions are safer and that high radiation doses and multiple procedures should be avoided.
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| 48. |
- Scholey, C., et al.
(författare)
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In-beam and decay spectroscopy of very neutron deficient iridium nuclei
- 2005
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Ingår i: Journal of Physics G. - : IOP Publishing. - 0954-3899 .- 1361-6471. ; 31:10, s. S1719-S1722
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Tidskriftsartikel (refereegranskat)abstract
- Iridium nuclei at and beyond the proton drip line have been studied via fusion evaporation reactions. A reaction of Mo-92(Kr-78, p2n) at a beam energy of 360 MeV and target thickness 500 mu g cm(-2) was employed to study (167,167m) Ir. A reaction of Sn-112(Ni-58, p2n) at a beam energy of 266 MeV and target thickness 500 mu g cm(-2) was used to study (169,169m) Ir. The experiments were performed at the University of Jyvaskyla utilizing the RITU separator in conjunction with the focal plane GREAT spectrometer and the JUROGAM Ge array at the target position. Excited states feeding. both the ground state and isomeric state in Ir-169, excited states feeding the ground state of Ir-167 and the ground state alpha decay of Re-165 have been observed for the first time along with excited states feeding (167)m Ir Experimental spectroscopic factors and reduced widths have been obtained for the proton and alpha decay of these nuclei.
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| 49. |
- Simon, H., et al.
(författare)
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Systematic investigation of the drip-line nuclei 11Li and 14Be and their unbound subsystems 10Li and 13Be
- 2007
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Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474. ; 791:3-4, s. 267-
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Tidskriftsartikel (refereegranskat)abstract
- Fragmentation reactions in a carbon target with beams of 11Li and 14Be at relativistic energies have been studied in a kinematically complete experiment at the ALADIN-LAND setup at GSI. Excited states in 11Li and 14Be were obtained from the data in the inelastic channel. The measured cross sections with the core nucleus in the final state show that in the 14Be case core polarization plays an important role. In the one-neutron knockout channels the measured angular correlations between fragment and neutron are asymmetric, which demonstrates the presence of states with different parities in the 11Li and 14Be ground states. For 10Li a low-lying virtual s-state, a p-state and evidence for a d-state could be extracted from the data, while the 12Be+n system shows resonances with more complicated structure.
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| 50. |
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