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2.
  • Borge, M. J. G., et al. (author)
  • Asymmetry in the super-allowed beta-transitions of the A=9 isobars
  • 2004
  • In: Nuclear Physics A. - : Elsevier BV. - 0375-9474. ; 738:1-4 SUPPL., s. 206-210
  • Journal article (peer-reviewed)abstract
    • We report here on the recent beta-decay studies of the A = 9 isobar made at ISOLDE/CERN. Mirror beta transitions in the A=9 chain are compared and a large asymmetry factor is deduced for the transitions to high excitation energy in Be-9 (11.8 MeV) and B-9 (12.2 MeV) fed in the beta-decay of Li-9 and C-9 respectively. It is shown that the asymmetry is not due to experimental problems or differences in the mechanisms of breakup or in the spin of the states. Only differences in the partial decay branches of the breakup channels have been found. As no asymmetry is found in the gs to gs transition it must be due to the particular structure of these excited states.
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3.
  • Fynbo, H. O. U., et al. (author)
  • News on C-12 from beta-decay studies
  • 2004
  • In: Nuclear Physics A. - : Elsevier BV. - 0375-9474. ; 738, s. 59-65
  • Conference paper (peer-reviewed)abstract
    • We discuss the importance of the spectroscopic properties of the resonances of C-12 just above the 3alpha-threshold, and review the existing experimental information of this region with emphasis on 0(+) and 2(+) states. A new experimental approach for studying the beta-decays of B-12 and N-12 is presented based on techniques developed in the context of Radioactive beam (rare isotope) physics. Finally preliminary results from an ongoing analysis of two recent experiments are given.
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4.
  • Fynbo, H. O. U., et al. (author)
  • Revised rates for the stellar triple-alpha process from measurement of C-12 nuclear resonances
  • 2005
  • In: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687 .- 1476-4679. ; 433:7022, s. 136-139
  • Journal article (peer-reviewed)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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7.
  • Bergmann, U. C., et al. (author)
  • Analysis of decay data from neutron-rich nuclei
  • 2001
  • In: European Physical Journal A. - 1434-601X .- 1434-6001. ; 11:3, s. 279-284
  • Journal article (peer-reviewed)abstract
    • The beta -decays of the neutron-rich nuclei Be-12 and Ne-29 have been studied. The statistical correlations between the almost identical half-lives of Be-12 and its daughter B-12 are analysed for a large sample of Be-12 decay data. Stringent mutual bounds are obtained on the parameter set, leading to a precise determination of the Be-12 half-life of 21.50 +/- 0.04 ms. From a simultaneous detection of beta -particles and neutrons from the decay of Ne-29 the neutron emission probability, P-n, is determined to 17 +/- 5%. No indication of two-neutron emission is seen from this nucleus. An upper limit of 2.2% (90% confidence level) is established for P-2n.
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8.
  • Bergmann, U. C., et al. (author)
  • On the beta-decay of C-9
  • 2001
  • In: Nuclear Physics A. - 0375-9474. ; 692:3-4, s. 427-450
  • Journal article (peer-reviewed)abstract
    • In beta -decay experiments on C-9 at CERN/ISOLDE the beta -strength was determined to the ground state, the 12.2 MeV excited state and the Isobaric Analog State (IAS) at 14.655 MeV in B-9. A large beta -strength asymmetry is deduced for the mirror transitions of C-9 and Li-9 to states around 12 MeV excitation energy. A satisfactory description of the three-body decay from a narrow energy region around the 12.2 MeV resonance is obtained within a sequential model involving the ground and first-excited states of Li-5 and Be-8. From the study of angular correlations the spin of the 12.2 MeV state is determined as 5/2(-). For the first time the population of the IAS is observed in beta -decay and new information on the decay of this state is obtained. The advantages of a closely packed. highly segmented detector setup are demonstrated. (C) 2001 Elsevier Science B.V. All rights reserved.
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9.
  • Borge, M. J. G., et al. (author)
  • Beta-delayed multiparticle emission studies at ISOL-type facilities
  • 2004
  • In: Nuclear Physics A. - : Elsevier BV. - 0375-9474. ; 746, s. 243-243
  • Conference paper (peer-reviewed)abstract
    • We report here on the recent beta-decay studies made at ISOL-type Facilities to determine the multiparticle breakup mechanism of excited states in light nuclei by studying them in full kinematics. In particular the results obtained for the A = 9 isobars and the breakup of the 12.7 MeV state in C-12 of unnatural parity are discussed. The breakup of the latter has been debated since more than a decade. Mirror beta transitions in the A = 9 chain are compared and a large asymmetry factor is deduced for the transitions to high excitation energy in Be-9 (11.8 MeV) and B-9 (12.2 MeV) fed in the beta-decay of Li-9 and C-9 respectively. It is shown that the asymmetry is not due to experimental problems or differences in the mechanisms of breakup or in the spin of the states. As no asymmetry is found in the gs to gs transition it must be due to the particular structure of these excited states. The controversy on the breakup mechanism of the 12.7 MeV state is resolved.
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10.
  • Diget, C. A., et al. (author)
  • Properties of the C-12 10 MeV state determined through beta-decay
  • 2005
  • In: Nuclear Physics A. - : Elsevier BV. - 0375-9474. ; 760:1-2, s. 3-18
  • Journal article (peer-reviewed)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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11.
  • Jeppesen, H. B., et al. (author)
  • News on beta delayed particle emission from Be-14
  • 2002
  • In: Progress of Theoretical Physics Supplement. - 0375-9687. ; :146, s. 520-524
  • Conference paper (peer-reviewed)abstract
    • Beta delayed charged particles from Be-14 have been measured and give an upper limit on beta delayed alpha particles of B(betaalpha)
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12.
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13.
  • Jeppesen, H., et al. (author)
  • News on beta delayed particle emission from 14Be
  • 2002
  • In: Progress of Theoretical Physics. - 0033-068X. ; :146 SUPPL., s. 520-524
  • Journal article (peer-reviewed)abstract
    • Beta delayed charged particles from 14Be have been measured and give an upper limit on beta delayed alpha particles of B(βα)<6.7×10-5 and a tentative branching ratio on beta delayed tritons of 7.5×10-5
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14.
  • Madurga, M., et al. (author)
  • Study of $[$beta$]$-delayed 3-body and 5-body breakup channels observed in the decay of 11Li
  • 2008
  • In: Nuclear Physics A. - : Elsevier BV. ; 810, s. 1-12
  • Journal article (peer-reviewed)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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15.
  • Madurga, M., et al. (author)
  • Study of β-delayed charged particle emission of 11Li: Evidence of new decay channels
  • 2008
  • In: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 111:1
  • Journal article (peer-reviewed)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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16.
  • Prezado, Y., et al. (author)
  • Large asymmetry in the strongest beta-transition for A=9
  • 2003
  • In: Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 576:1-2, s. 55-61
  • Journal article (peer-reviewed)abstract
    • A new measurement of the beta-decay of Li-9 has clarified the feeding to the highest accessible states in Be-9. It is found that the P-decay mainly populates the 11.8 MeV state, whose spin is determined as 5/2(-). The extracted B-GT value of 5.3(0.9) is a factor 4.4(1.0) larger than that of the mirror transition from C-9. A theoretical explanation of such a pronounced beta-decay asymmetry is presently lacking. (C) 2003 Elsevier B.V. All rights reserved.
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19.
  • Shergur, J., et al. (author)
  • beta-decay studies of Sn135-137 using selective resonance laser ionization techniques
  • 2002
  • In: Physical Review C - Nuclear Physics. - 2469-9985 .- 2469-9993. ; 65:3
  • Journal article (peer-reviewed)abstract
    • The decays of the very neutron rich Sn isotopes Sn135-137 were studied at CERN/ISOLDE using isotopic and isobaric selectivity achieved by the use of a resonance ionization laser ion source and mass spectroscopy, respectively. Neutron decay rates, gamma-ray singles, and gamma-gamma coincidence data were collected as a function of time. The half-life (T-1/2) and delayed neutron emission probability (P-n) values of 135 Sn were measured to be 530(20) ms and 21(3)%, respectively. For Sn-136, a T-1/2 of 250(30) ms was determined along with a P-n value of 30(5)%. For Sn-137, a T-1/2 of 190(60) ms and a P-n value of 58(15)% were deduced. Identification of low-energy transitions in Sb-135 was made possible by comparison of laser-on and laser-off gamma-ray spectra. Those data combined with gamma-gamma coincidence spectra were used to construct a level scheme for Sb-135 that includes an unexpectedly low first excited state at 282 keV. A ground state beta branch of 33.2% was measured by following the growth and decay of the Sb-135 daughter. Shell-model calculations are consistent with the observed Sb-135 level structure and can account for a lowered first excited state.
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20.
  • Cooney, M T, et al. (author)
  • HDL cholesterol protects against cardiovascular disease in both genders, at all ages and at all levels of risk.
  • 2009
  • In: Atherosclerosis. - : Elsevier BV. - 1879-1484 .- 0021-9150. ; 206:2, s. 611-6
  • Journal article (peer-reviewed)abstract
    • OBJECTIVE: We aimed to clarify some previous inconsistencies regarding the role of high density lipoprotein cholesterol (HDL-C) as a CVD protective factor. METHODS: The SCORE dataset contained data on HDL-C for 104,961 individuals (45% women) without pre-existing coronary heart disease (CHD). These were from 7 pooled European prospective studies. The effect of HDL-C, both in quintiles and as a continuous variable, on risk of CVD and CHD mortality was examined, using Cox proportional hazards model, adjusted for age, total cholesterol, systolic blood pressure, smoking, diabetes and body mass index and stratified by gender, age group, country and category of SCORE CVD risk. RESULTS: A strong, graded, independent, inverse relationship between HDL-C and both CVD and CHD mortality was demonstrated. Adjusted hazard ratios per 0.5mmol/l increase in HDL-C were 0.60 (0.51, 0.69) and 0.76 (0.70, 0.83) in women and men, respectively for the CVD mortality endpoint. The corresponding hazard ratios were 0.53 (0.42, 0.68) and 0.79 (0.64, 0.98) in elderly women and men, respectively. The relationship was significant in all SCORE CVD risk strata and age groups. CONCLUSIONS: This multivariable analysis, the largest of its kind to date, has confirmed the inverse, independent, strong and graded relationship between HDL-C and both CVD and CHD mortality. We have clarified previous suggestions that the relationship is stronger in women and that it applies in all age groups. This is the first prospective study to demonstrate the independent relationship specifically in healthy elderly women and to show that the relationship holds at all levels of total CVD risk.
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21.
  • Danesh, John, et al. (author)
  • Plasma fibrinogen level and the risk of major cardiovascular diseases and nonvascular mortality: an individual participant meta-analysis
  • 2005
  • In: JAMA: The Journal of the American Medical Association. - : American Medical Association (AMA). - 1538-3598 .- 0098-7484. ; 294:14, s. 1799-1809
  • Research review (peer-reviewed)abstract
    • CONTEXT: Plasma fibrinogen levels may be associated with the risk of coronary heart disease (CHD) and stroke. OBJECTIVE: To assess the relationships of fibrinogen levels with risk of major vascular and with risk of nonvascular outcomes based on individual participant data. DATA SOURCES: Relevant studies were identified by computer-assisted searches, hand searches of reference lists, and personal communication with relevant investigators. STUDY SELECTION: All identified prospective studies were included with information available on baseline fibrinogen levels and details of subsequent major vascular morbidity and/or cause-specific mortality during at least 1 year of follow-up. Studies were excluded if they recruited participants on the basis of having had a previous history of cardiovascular disease; participants with known preexisting CHD or stroke were excluded. DATA EXTRACTION: Individual records were provided on each of 154,211 participants in 31 prospective studies. During 1.38 million person-years of follow-up, there were 6944 first nonfatal myocardial infarctions or stroke events and 13,210 deaths. Cause-specific mortality was generally available. Analyses involved proportional hazards modeling with adjustment for confounding by known cardiovascular risk factors and for regression dilution bias. DATA SYNTHESIS: Within each age group considered (40-59, 60-69, and > or =70 years), there was an approximately log-linear association with usual fibrinogen level for the risk of any CHD, any stroke, other vascular (eg, non-CHD, nonstroke) mortality, and nonvascular mortality. There was no evidence of a threshold within the range of usual fibrinogen level studied at any age. The age- and sex- adjusted hazard ratio per 1-g/L increase in usual fibrinogen level for CHD was 2.42 (95% confidence interval [CI], 2.24-2.60); stroke, 2.06 (95% CI, 1.83-2.33); other vascular mortality, 2.76 (95% CI, 2.28-3.35); and nonvascular mortality, 2.03 (95% CI, 1.90-2.18). The hazard ratios for CHD and stroke were reduced to about 1.8 after further adjustment for measured values of several established vascular risk factors. In a subset of 7011 participants with available C-reactive protein values, the findings for CHD were essentially unchanged following additional adjustment for C-reactive protein. The associations of fibrinogen level with CHD or stroke did not differ substantially according to sex, smoking, blood pressure, blood lipid levels, or several features of study design. CONCLUSIONS: In this large individual participant meta-analysis, moderately strong associations were found between usual plasma fibrinogen level and the risks of CHD, stroke, other vascular mortality, and nonvascular mortality in a wide range of circumstances in healthy middle-aged adults. Assessment of any causal relevance of elevated fibrinogen levels to disease requires additional research.
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22.
  • Diget, C. A., et al. (author)
  • Breakup channels for C-12 triple-alpha continuum states
  • 2009
  • In: Physical Review C - Nuclear Physics. - 2469-9985 .- 2469-9993. ; 80:3
  • Journal article (peer-reviewed)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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23.
  • Emerging Risk Factors, Collaboration, et al. (author)
  • The Emerging Risk Factors Collaboration: analysis of individual data on lipid, inflammatory and other markers in over 1.1 million participants in 104 prospective studies of cardiovascular diseases
  • 2007
  • In: Eur J Epidemiol. - 0393-2990. ; 22:12, s. 839-69
  • Journal article (peer-reviewed)abstract
    • Many long-term prospective studies have reported on associations of cardiovascular diseases with circulating lipid markers and/or inflammatory markers. Studies have not, however, generally been designed to provide reliable estimates under different circumstances and to correct for within-person variability. The Emerging Risk Factors Collaboration has established a central database on over 1.1 million participants from 104 prospective population-based studies, in which subsets have information on lipid and inflammatory markers, other characteristics, as well as major cardiovascular morbidity and cause-specific mortality. Information on repeat measurements on relevant characteristics has been collected in approximately 340,000 participants to enable estimation of and correction for within-person variability. Re-analysis of individual data will yield up to approximately 69,000 incident fatal or nonfatal first ever major cardiovascular outcomes recorded during about 11.7 million person years at risk. The primary analyses will involve age-specific regression models in people without known baseline cardiovascular disease in relation to fatal or nonfatal first ever coronary heart disease outcomes. This initiative will characterize more precisely and in greater detail than has previously been possible the shape and strength of the age- and sex-specific associations of several lipid and inflammatory markers with incident coronary heart disease outcomes (and, secondarily, with other incident cardiovascular outcomes) under a wide range of circumstances. It will, therefore, help to determine to what extent such associations are independent from possible confounding factors and to what extent such markers (separately and in combination) provide incremental predictive value.
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24.
  • Fynbo, H. O. U., et al. (author)
  • New information on the beta-decay of Li-11 from Doppler broadened gamma lines
  • 2004
  • In: Nuclear Physics A. - : Elsevier BV. - 0375-9474. ; 736:1-2, s. 39-54
  • Journal article (peer-reviewed)abstract
    • The gamma-ray spectrum following beta-decay of Li-11 has been remeasured at the ISOLDE facility at CERN. Two new transitions were observed through the use of large Ge-detectors. Most gamma-decays will follow beta-delayed neutron emission. Information on the energy of the neutron is derived from analysis of the gamma line-shape and used to construct a partial decay scheme for Li-11. Lifetime values for the 1(-) and 2(-) levels in Be-10 are also derived. A new partial decay scheme is presented. (C) 2004 Elsevier B.V. All rights reserved.
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25.
  • Fynbo, H. O. U., et al. (author)
  • The β-decay approach for studying 12C
  • 2008
  • In: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 111:1
  • Journal article (peer-reviewed)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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26.
  • Gregson, J., et al. (author)
  • Cardiovascular Risk Factors Associated With Venous Thromboembolism
  • 2019
  • In: JAMA Cardiology. - : American Medical Association (AMA). - 0965-2590 .- 2380-6583 .- 2380-6591. ; 4:2, s. 163-173
  • Journal article (peer-reviewed)abstract
    • IMPORTANCE It is uncertain to what extent established cardiovascular risk factors are associated with venous thromboembolism (VTE). OBJECTIVE To estimate the associations of major cardiovascular risk factors with VTE, ie, deep vein thrombosis and pulmonary embolism. DESIGN, SETTING, AND PARTICIPANTS This study included individual participant data mostly from essentially population-based cohort studies from the Emerging Risk Factors Collaboration (ERFC; 731728 participants; 75 cohorts; years of baseline surveys, February 1960 to June 2008; latest date of follow-up, December 2015) and the UK Biobank (421537 participants; years of baseline surveys, March 2006 to September 2010; latest date of follow-up, February 2016). Participants without cardiovascular disease at baseline were included. Data were analyzed from June 2017 to September 2018. MAIN OUTCOMES AND MEASURES Hazard ratios (HRs) per 1-SD higher usual risk factor levels (or presence/absence). Incident fatal outcomes in ERFC (VTE, 1041; coronary heart disease [CND], 25131) and incident fatal/nonfatal outcomes in UK Biobank (VTE, 2321; CHD, 3385). Hazard ratios were adjusted for age, sex, smoking status, diabetes, and body mass index (BMI). RESULTS Of the 731728 participants from the ERFC. 403 396 (55.1%) were female, and the mean (SD) age at the time of the survey was 51.9 (9.0) years; of the 421537 participants from the UK Biobank, 233 699 (55.4%) were female, and the mean (SD) age at the time of the survey was 56.4 (8.1) years. Risk factors for VTE included older age (ERFC: HR per decade, 2.67; 95% CI, 2.45-2.91; UK Biobank: HR, 1.81; 95% CI, 1.71-1.92), current smoking (ERFC: HR, 1.38; 95% CI, 1.20-1.58; UK Biobank: HR, 1.23; 95% CI, 1.08-1.40), and BMI (ERFC: HR per 1-SD higher BMI, 1.43; 95% CI, 1.35-1.50; UK Biobank: HR, 1.37; 95% CI, 1.32-1.41). For these factors, there were similar HRs for pulmonary embolism and deep vein thrombosis in UK Biobank (except adiposity was more strongly associated with pulmonary embolism) and similar HRs for unprovoked vs provoked VTE. Apart from adiposity, these risk factors were less strongly associated with VTE than CHD. There were inconsistent associations of VTEs with diabetes and blood pressure across ERFC and UK Biobank, and there was limited ability to study lipid and inflammation markers. CONCLUSIONS AND RELEVANCE Older age, smoking, and adiposity were consistently associated with higher VTE risk.
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28.
  • Hagman, A., et al. (author)
  • Obstetric Outcomes in Women With Turner Karyotype EDITORIAL COMMENT
  • 2012
  • In: Obstetrical and Gynecological Survey. - 0029-7828. ; 67:4, s. 228-229
  • Journal article (other academic/artistic)abstract
    • There is concern over the high risk of cardiovascular complications, hypertensive disorders, and other adverse obstetric outcomes among pregnant women with Turner syndrome (TS). A diagnosis of TS is made in some women late in life or not at all. Spontaneous pregnancies are rare in women with TS and are associated with a high rate of complications, especially miscarriage. The use of assisted reproductive techniques is an option for these women; pregnancy and implantation rates after oocyte donation in women with TS seem to be comparable with those without TS who need this treatment. Few data are available on obstetric outcome in pregnant women with TS. The aim of this retrospective population-based cohort study was to compare maternal and neonatal outcomes among singleton pregnancies of women with and without TS. Data on births occurring between 1973 and 2007 from the Swedish Genetic Turner Register and the Swedish Medical Birth Register were cross-linked. Obstetric outcome in infants born to women with TS was compared with a reference group of 56,000 women from the general population. Mean gestational age and birth weight were adjusted for maternal age. Outcome in TS women with twins was described separately. A total of 115 women with TS gave birth to 208 children (202 singletons and 3 sets of twins) during the study period. The TS diagnosis was unknown in 52% of the women before the first delivery. Women in the TS group were older at the first delivery than women in the reference group; median age was 30 years and 26 years, respectively (P < 0.0001). There was a trend toward more women with TS having preeclampsia during their first pregnancy (6.3 vs. 3.0%; P = 0.07). One woman suffered from an aortic dissection during her second spontaneous pregnancy. Compared with the reference group, the median gestational age was shorter in children in the TS group (-6.4 days, P = 0.0067), and median birth weight was lower (-208 g, P = 0.001); however, no significant difference was found in median standard deviation scores for weight and length at birth. The rate of cesarean delivery was higher in the TS group than in the reference group (35.6% vs. 11.8%, respectively, P < 0.0001). There was no significant difference in birth defects between groups. These findings show that women with a TS karyotype have mostly favorable obstetric outcomes. Singletons of women with TS have a shorter gestational age but a similar size at birth. The data also show no difference in birth defects between women with and without TS.
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29.
  • Hyldegaard, S., et al. (author)
  • Branching ratios in the beta decays of N-12 and B-12
  • 2009
  • In: Physical Review C - Nuclear Physics. - 2469-9985 .- 2469-9993. ; 80:4
  • Journal article (peer-reviewed)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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30.
  • Hyldegaard, S., et al. (author)
  • Precise branching ratios to unbound 12C states from 12N and 12B [beta]-decays
  • 2009
  • In: Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 678:5, s. 459 - 464
  • Journal article (peer-reviewed)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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31.
  • Hyldegaard, S., et al. (author)
  • R-matrix analysis of the beta decays of 12N and 12B
  • 2010
  • In: Physical Review C - Nuclear Physics. - 2469-9985 .- 2469-9993. ; 81:2
  • Journal article (peer-reviewed)abstract
    • The β decays of 12N and 12B have been studied at KVI and JYFL to resolve the composition of the broad and interfering 0+ and 2+ strengths in the triple-α continuum. For the first time a complete treatment of 3α decay is presented including all major breakup channels. A multilevel, many-channel R-matrix formalism has been developed for the complete description of the breakup in combination with the recently published separate analysis of angular correlations. We find that, in addition to the Hoyle state at 7.65 MeV, more than one 0+ and 2+ state is needed to reproduce the spectra. Broad 03+ and 22+ states are found between 10.5 and 12 MeV in this work. The presence of β strength up to the 12N Q-value window suggests the presence of additional 0+ and 2+ components in the 12C structure at energies above 12.7 MeV.
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32.
  • Knudsen, H. H., et al. (author)
  • Beta-decay of 13O
  • 2005
  • In: Physical Review C - Nuclear Physics. - 2469-9985 .- 2469-9993. ; 72:4, s. 044312-
  • Journal article (peer-reviewed)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.
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35.
  • Oinonen, M., et al. (author)
  • Non-analog beta decay of Rb-74
  • 2001
  • In: Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 0370-2693. ; 511:2-4, s. 145-150
  • Journal article (peer-reviewed)abstract
    • The magnitude of the Coulomb mixing parameter delta (l)(IM) has been experimentally deduced, for the first time, for the B decay of Rb-74. Th, estimated magnitude is derived from the feeding of the non-analog first excited 0(+) state in Kr-74. The inferred upper Limit of 0.07% is small compared to theoretical predictions. The half-life was measured to be 64.90(9) ms.
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36.
  • Prezado, Y., et al. (author)
  • Low-lying resonance states in the Be-9 continuum
  • 2005
  • In: Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 618:1-4, s. 43-50
  • Journal article (peer-reviewed)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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37.
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38.
  • Shergur, J., et al. (author)
  • Decay of Sn-135,Sn-136 isolated by use of a laser ion source and evidence for a more harmonic-oscillator-like nuclear potential
  • 2001
  • In: Nuclear Physics A. - 0375-9474. ; 682, s. 493C-497C
  • Conference paper (peer-reviewed)abstract
    • The use of a resonance ionization laser ion source at CERN/ISOLDE has made it possible to study the decay of very neutron-rich Sn135-137. The decay of Sn-135 is found to populate low-energy levels in Sb-135 via direct beta decay and the first excited state in Sb-134 by beta-delayed neutron emission. The level structure of Sb-135 Will be discussed and a possible signature for a more diffuse nuclear surface considered.
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39.
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