| 1. |
- Zheng, Y., et al.
(författare)
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gamma-ray linear polarization measurements and (g(9/2))(-3) neutron alignment in Ru-91
- 2013
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Ingår i: Physical Review C. Nuclear Physics. - : American Physical Society (APS). - 0556-2813 .- 1089-490X. ; 87:4, s. 044328-
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Tidskriftsartikel (refereegranskat)abstract
- Linear polarization measurements have been performed for gamma rays in Ru-91 produced with the Ni-58(Ar-36,2p1n gamma)Ru-91 reaction at a beam energy of 111 MeV. The EXOGAM Ge clover array has been used to measure the gamma-gamma coincidences, gamma-ray linear polarization, and gamma-ray angular distributions. The polarization sensitivity of the EXOGAM clover detectors acting as Compton polarimeters has been determined in the energy range 0.3-1.3 MeV. Several transitions have been observed for the first time. Measurements of linear polarization and angular distribution have led to the firm assignments of spin differences and parity of high-spin states in Ru-91. More specifically, calculations using a semiempirical shell model were performed to understand the structures of the first and second (21/2(+)) and (17/2(+)) levels. The results are in good agreement with the experimental data, supporting the interpretation of the nonyrast (21/2(+)) and (17/2(+)) states in terms of the J(max) and J(max) - 2 members of the seniority-three nu(g(9/2))(-3) multiplet.
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| 2. |
- Cederwall, Bo, et al.
(författare)
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Evidence for a spin-aligned neutron-proton paired phase from the level structure of 92Pd
- 2011
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 469:7328, s. 68-71
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Tidskriftsartikel (refereegranskat)abstract
- Shell structure and magic numbers in atomic nuclei were generally explained by pioneering work(1) that introduced a strong spin-orbit interaction to the nuclear shell model potential. However, knowledge of nuclear forces and the mechanisms governing the structure of nuclei, in particular far from stability, is still incomplete. In nuclei with equal neutron and proton numbers (N = Z), enhanced correlations arise between neutrons and protons (two distinct types of fermions) that occupy orbitals with the same quantum numbers. Such correlations have been predicted to favour an unusual type of nuclear superfluidity, termed isoscalar neutron-proton pairing(2-6), in addition to normal isovector pairing. Despite many experimental efforts, these predictions have not been confirmed. Here we report the experimental observation of excited states in the N = Z = 46 nucleus Pd-92. Gamma rays emitted following the Ni-58(Ar-36,2n)Pd-92 fusion-evaporation reaction were identified using a combination of state-of-the-art high-resolution c-ray, charged-particle and neutron detector systems. Our results reveal evidence for a spin-aligned, isoscalar neutron-proton coupling scheme, different from the previous prediction(2-6). We suggest that this coupling scheme replaces normal superfluidity (characterized by seniority coupling(7,8)) in the ground and low-lying excited states of the heaviest N = Z nuclei. Such strong, isoscalar neutron-proton correlations would have a considerable impact on the nuclear level structure and possibly influence the dynamics of rapid proton capture in stellar nucleosynthesis.
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| 3. |
- Mason, P, et al.
(författare)
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Octupole signatures in Ba-124,Ba-125
- 2005
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Ingår i: Journal of Physics G. - : IOP Publishing. - 0954-3899 .- 1361-6471. ; 31:10, s. S1729-S1733
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Tidskriftsartikel (refereegranskat)abstract
- The gamma decay of the nuclei Ba-121,Ba-125 has been investigated with the EUROBALL array, using the reaction Ni-64+Ni-64 at E-beam = 255 and 261 MeV. Six new E1 transitions have been found in the nucleus Ba-125, suggesting a significant role of octupole correlations in the origin of its parity doublets. The J(pi) = 3(-) level of the nucleus Ba-124 has been identified for the first time. Its excitation energy is in very good agreement with a prediction based on a microscopic model including octupole interactions.
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| 4. |
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| 5. |
- Bondy, M L, et al.
(författare)
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Brain tumor epidemiology : Consensus from the Brain Tumor Epidemiology Consortium
- 2008
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Ingår i: Cancer. - : Wiley. - 0008-543X .- 1097-0142. ; 113, s. 1953-1968
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Tidskriftsartikel (refereegranskat)abstract
- Epidemiologists in the Brain Tumor Epidemiology Consortium (BTEC) have prioritized areas for further research. Although many risk factors have been examined over the past several decades, there are few consistent findings, possibly because of small sample sizes in individual studies and differences between studies in patients, tumor types, and methods of classification. Individual studies generally have lacked samples of sufficient size to examine interactions. A major priority based on available evidence and technologies includes expanding research in genetics and molecular epidemiology of brain tumors. BTEC has taken an active role in Promoting understudied groups, such as pediatric brain tumors; the etiology of rare glioma subtypes, such as oligodendroglioma; and meningioma, which, although it is not uncommon, has only recently, been registered systematically in the United States. There also is a pressing need for more researchers, especially junior investigators, to study brain tumor epidemiology. However, relatively poor funding for brain tumor research has made it difficult to encourage careers in this area. In this report, BTEC epidemiologists reviewed the groups Consensus oil the Current state of scientific findings, and they present a consensus oil research priorities to identify which important areas the science should move to address.
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| 6. |
- Amirian, E. Susan, et al.
(författare)
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Aspirin, NSAIDs, and Glioma Risk : Original Data from the Glioma International Case-Control Study and a Meta-analysis
- 2019
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Ingår i: Cancer Epidemiology, Biomarkers and Prevention. - : American Association for Cancer Research (AACR). - 1055-9965 .- 1538-7755. ; 28:3, s. 555-562
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Tidskriftsartikel (refereegranskat)abstract
- Background: There have been few studies of sufficient size to address the relationship between glioma risk and the use of aspirin or NSAIDs, and results have been conflicting. The purpose of this study was to examine the associations between glioma and aspirin/NSAID use, and to aggregate these findings with prior published studies using meta-analysis.Methods: The Glioma International Case-Control Study (GICC) consists of 4,533 glioma cases and 4,171 controls recruited from 2010 to 2013. Interviews were conducted using a standardized questionnaire to obtain information on aspirin/NSAID use. We examined history of regular use for ≥6 months and duration-response. Restricted maximum likelihood meta-regression models were used to aggregate site-specific estimates, and to combine GICC estimates with previously published studies.Results: A history of daily aspirin use for ≥6 months was associated with a 38% lower glioma risk, compared with not having a history of daily use [adjusted meta-OR = 0.62; 95% confidence interval (CI), 0.54–0.70]. There was a significant duration-response trend (P = 1.67 × 10−17), with lower ORs for increasing duration of aspirin use. Duration-response trends were not observed for NSAID use. In the meta-analysis aggregating GICC data with five previous studies, there was a marginally significant association between use of aspirin and glioma (mOR = 0.84; 95% CI, 0.70–1.02), but no association for NSAID use.Conclusions: Our study suggests that aspirin may be associated with a reduced risk of glioma.Impact: These results imply that aspirin use may be associated with decreased glioma risk. Further research examining the association between aspirin use and glioma risk is warranted.
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| 7. |
- Dahlin, Anna M., 1979-, et al.
(författare)
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A genome-wide association study on medulloblastoma
- 2020
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Ingår i: Journal of Neuro-Oncology. - : Springer. - 0167-594X .- 1573-7373. ; 147:2, s. 309-315
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: Medulloblastoma is a malignant embryonal tumor of the cerebellum that occurs predominantly in children. To find germline genetic variants associated with medulloblastoma risk, we conducted a genome-wide association study (GWAS) including 244 medulloblastoma cases and 247 control subjects from Sweden and Denmark.Methods: Genotyping was performed using Illumina BeadChips, and untyped variants were imputed using IMPUTE2.Results: Fifty-nine variants in 11 loci were associated with increased medulloblastoma risk (p < 1 × 10–5), but none were statistically significant after adjusting for multiple testing (p < 5 × 10–8). Thirteen of these variants were genotyped, whereas 46 were imputed. Genotyped variants were further investigated in a validation study comprising 249 medulloblastoma cases and 629 control subjects. In the validation study, rs78021424 (18p11.23, PTPRM) was associated with medulloblastoma risk with OR in the same direction as in the discovery cohort (ORT = 1.59, pvalidation = 0.02). We also selected seven medulloblastoma predisposition genes for investigation using a candidate gene approach: APC, BRCA2, PALB2, PTCH1, SUFU, TP53, and GPR161. The strongest evidence for association was found for rs201458864 (PALB2, ORT = 3.76, p = 3.2 × 10–4) and rs79036813 (PTCH1, ORA = 0.42, p = 2.6 × 10–3).Conclusion: The results of this study, including a novel potential medulloblastoma risk loci at 18p11.23, are suggestive but need further validation in independent cohorts.
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| 8. |
- Lupo, Philip J., et al.
(författare)
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Perinatal and familial risk factors for soft tissue sarcomas in childhood through young adulthood : a population-based assessment in 4 million live births
- 2020
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Ingår i: International Journal of Cancer. - : John Wiley & Sons. - 0020-7136 .- 1097-0215. ; 146:3, s. 791-802
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Tidskriftsartikel (refereegranskat)abstract
- Perinatal factors have been associated with soft tissue sarcomas (STS) in case-control studies. However, (i) the contributions of factors including fetal growth remain unknown, (ii) these factors have not been examined in cohort studies and (iii) few assessments have evaluated risk in specific STS subtypes. We sought to identify the role of perinatal and familial factors on the risk of STS in a large population-based birth cohort. We identified 4,023,436 individuals in the Swedish Birth Registry born during 1973-2012. Subjects were linked to the Swedish Cancer Registry, where incident STS cases were identified. We evaluated perinatal and familial factors obtained from Statistics Sweden, including fetal growth, gestational age, and presence of a congenital malformation. Poisson regression was used to estimate incidence rate ratios (IRRs) and 95% confidence intervals (CIs) for associations between perinatal factors and STS overall, as well as by common subtypes. There were 673 individuals diagnosed with STS in 77.5 million person-years of follow-up. Having a congenital malformation was associated with STS (IRR = 1.70, 95% CI: 1.23-2.35). This association was stronger (IRR = 2.90, 95% CI: 1.25-6.71) in recent years (2000-2012). Low fetal growth was also associated with STS during the same time period (IRR = 1.86, 95% CI: 1.05-3.29). Being born preterm was associated with rhabdomyosarcoma (IRR = 1.74, 95% CI: 1.08-2.79). In our cohort study, those with congenital malformations and other adverse birth outcomes were more likely to develop a STS compared to their unaffected contemporaries. These associations may point to disrupted developmental pathways and genetic factors influencing the risk of STS.
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| 9. |
- Marcotte, Erin L., et al.
(författare)
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Caesarean delivery and risk of childhood leukaemia : a pooled analysis from the Childhood Leukemia International Consortium (CLIC)
- 2016
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Ingår i: The Lancet Haematology. - 2352-3026. ; 3:4, s. E176-E185
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Tidskriftsartikel (refereegranskat)abstract
- Background Results from case-control studies have shown an increased risk of acute lymphoblastic leukaemia (ALL) in young children born by caesarean delivery, and prelabour caesarean delivery in particular; however, an association of method of delivery with childhood leukaemia subtypes has yet to be established. We therefore did a pooled analysis of data to investigate the association between childhood leukaemia and caesarean delivery. Methods We pooled data from 13 case-control studies from the Childhood Leukemia International Consortium done in nine countries (Canada, Costa Rica, Egypt, France, Germany, Greece, Italy, New Zealand, and the USA) for births from 1970-2013. We analysed caesarean delivery overall and by indications that probably resulted in prelabour caesarean delivery or emergency caesarean delivery. We used multivariable logistic regression models, adjusted for child's birthweight, sex, age, ethnic origin, parental education, maternal age, and study, to estimate odds ratios (ORs) and 95% CIs for the risk of ALL and acute myeloid leukaemia (AML) in children aged 0-14 years at diagnosis. Findings The studies provided data for 8780 ALL cases, 1332 AML cases, and 23 459 controls, of which the birth delivery method was known for 8655 (99%) ALL cases, 1292 (97%) AML cases, and 23 351 (> 99%) controls. Indications for caesarean delivery were available in four studies (there were caesarean deliveries for 1061 of 4313 ALL cases, 138 of 664 AML cases, and 1401 of 5884 controls). The OR for all indications of caesarean delivery and ALL was 1.06 (95% CI 0.99-1.13), and was significant for prelabour caesarean delivery and ALL (1.23 [1.04-1.47]; p= 0.018). Emergency caesarean delivery was not associated with ALL (OR 1.02 [95% CI 0.81-1.30]). AML was not associated with caesarean delivery (all indications OR 0.99 [95% CI 0.84-1.17]; prelabour caesarean delivery 0.83 [0.54-1.26]; and emergency caesarean delivery 1.05 [0.63-1.77]). Interpretation Our results suggest an increased risk of childhood ALL after prelabour caesarean delivery. If this association is causal, maladaptive immune activation due to an absence of stress response before birth in children born by prelabour caesarean delivery could be considered as a potential mechanism.
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| 10. |
- McCarthy, Bridget J, et al.
(författare)
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Risk factors for oligodendroglial tumors : A pooled international study
- 2011
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Ingår i: Neuro-Oncology. - Charlottesville, VA : Carden Jennings Pub.. - 1522-8517 .- 1523-5866. ; 13:2, s. 242-250
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Tidskriftsartikel (refereegranskat)abstract
- Oligodendroglial tumors are rare subtypes of brain tumors and are often combined with other glial tumors in epidemiological analyses. However, different demographic associations and clinical characteristics suggest potentially different risk factors. The purpose of this study was to investigate possible risk factors for oligodendroglial tumors (including oligodendroglioma, anaplastic oligodendroglioma, and mixed glioma). Data from 7 case-control studies (5 US and 2 Scandinavian) were pooled. Unconditional logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs), adjusted for age group, gender, and study site. Data on 617 cases and 1260 controls were available for analyses. Using data from all 7 studies, history of allergies and/or asthma was associated with a decreased risk of anaplastic oligodendroglioma (OR = 0.6; 95% CI: 0.4-0.9), and history of asthma only was associated with a decreased risk of oligodendroglioma (OR = 0.5; 95% CI: 0.3-0.9) and anaplastic oligodendroglioma (OR = 0.3; 95% CI: 0.1-0.9). A family history of brain tumors was associated with an increased risk of anaplastic oligodendroglioma (OR = 2.2; 95% CI: 1.1-4.5). Having had chicken pox was associated with a decreased risk of oligodendroglioma (OR = 0.6; 95% CI: 0.4-0.9) and anaplastic oligodendroglioma (OR = 0.5; 95% CI: 0.3-0.9) in the US studies. Although there is some overlap in risk factors between oligodendroglial tumors and gliomas as a group, it is likely that additional factors specific to oligodendroglial tumors have yet to be identified. Large, multi-institution international studies will be necessary to better characterize these etiological risk factors.
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