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  • Abdallah, J., et al. (författare)
  • A study of the b-quark fragmentation function with the DELPHI detector at LEP I and an averaged distribution obtained at the Z Pole
  • 2011
  • Ingår i: European Physical Journal C. - 1434-6044. ; 71:2, s. 1557
  • Tidskriftsartikel (refereegranskat)abstract
    • The nature of b-quark jet hadronisation has been investigated using data taken at the Z peak by the DELPHI detector at LEP. Two complementary methods are used to reconstruct the energy of weakly decaying b-hadrons, E-B(weak). The average value of x(B)(weak) = E-B(weak)/E-beam is measured to be 0.699 +/- 0.011. The resulting x(B)(weak) distribution is then analysed in the framework of two choices for the perturbative contribution (parton shower and Next to Leading Log QCD calculation) in order to extract measurements of the non-perturbative contribution to be used in studies of b-hadron production in other experimental environments than LEP. In the parton shower framework, data favour the Lund model ansatz and corresponding values of its parameters have been determined within PYTHIA 6.156 from DELPHI data: a = 1.84(-0.21)(+0.23) and b = 0.642(-0.063)(+0.073) GeV-2, with a correlation factor rho = 92.2%. Combining the data on the b-quark fragmentation distributions with those obtained at the Z peak by ALEPH, OPAL and SLD, the average value of x(B)(weak) is found to be 0.7092 +/- 0.0025 and the non-perturbative fragmentation component is extracted. Using the combined distribution, a better determination of the Lund parameters is also obtained: a = 1.48(-0.10)(+0.11) and b = 0.509(-0.023)(+0.024) GeV-2, with a correlation factor rho = 92.6%.
  • Abdallah, J., et al. (författare)
  • Measurement of the electron structure function F-2(e) at LEP energies
  • 2014
  • Ingår i: Physics Letters B. - 0370-2693. ; 737, s. 39-47
  • Tidskriftsartikel (refereegranskat)abstract
    • The hadronic part of the electron structure function F-2(e) has been measured for the first time, using e(+)e(-) data collected by the DELPHI experiment at LEP, at centre-of-mass energies of root s = 91.2-209.5 GeV. The data analysis is simpler than that of the measurement of the photon structure function. The electron structure function F-2(e) data are compared to predictions of phenomenological models based on the photon structure function. It is shown that the contribution of large target photon virtualities is significant. The data presented can serve as a cross-check of the photon structure function F-2(gamma) analyses and help in refining existing parameterisations.
  • Abdallah, J., et al. (författare)
  • Search for single top quark production via contact interactions at LEP2
  • 2011
  • Ingår i: European Physical Journal C. - 1434-6044. ; 71:2, s. 1555
  • Tidskriftsartikel (refereegranskat)abstract
    • Single top quark production via four-fermion contact interactions associated to flavour-changing neutral currents was searched for in data taken by the DELPHI detector at LEP2. The data were accumulated at centre-of-mass energies ranging from 189 to 209 GeV, with an integrated luminosity of 598.1 pb(-1). No evidence for a signal was found. Limits on the energy scale Lambda, were set for scalar-, vector- and tensor-like coupling scenarios.
  • Abdallah, J., et al. (författare)
  • Study of the dependence of direct soft photon production on the jet characteristics in hadronic Z (0) decays
  • 2010
  • Ingår i: European Physical Journal C. - 1434-6044. ; 67:3-4, s. 343-366
  • Tidskriftsartikel (refereegranskat)abstract
    • An analysis of the direct soft photon production rate as a function of the parent jet characteristics is presented, based on hadronic events collected by the DELPHI experiment at LEP1. The dependences of the photon rates on the jet kinematic characteristics (momentum, mass, etc.) and on the jet charged, neutral and total hadron multiplicities are reported. Up to a scale factor of about four, which characterizes the overall value of the soft photon excess, a similarity of the observed soft photon behavior to that of the inner hadronic bremsstrahlung predictions is found for the momentum, mass, and jet charged multiplicity dependences. However for the dependence of the soft photon rate on the jet neutral and total hadron multiplicities a prominent difference is found for the observed soft photon signal as compared to the expected bremsstrahlung from final state hadrons. The observed linear increase of the soft photon production rate with the jet total hadron multiplicity and its strong dependence on the jet neutral multiplicity suggest that the rate is proportional to the number of quark pairs produced in the fragmentation process, with the neutral pairs being more effectively radiating than the charged ones.
  • Gapstur, S. M., et al. (författare)
  • Menopausal hormone use and ovarian cancer risk: individual participant meta-analysis of 52 epidemiological studies
  • 2015
  • Ingår i: The Lancet. - Elsevier. - 1474-547X .- 0140-6736. ; 385:9980, s. 1835-1842
  • Tidskriftsartikel (refereegranskat)abstract
    • Background Half the epidemiological studies with information about menopausal hormone therapy and ovarian cancer risk remain unpublished, and some retrospective studies could have been biased by selective participation or recall. We aimed to assess with minimal bias the effects of hormone therapy on ovarian cancer risk. Methods Individual participant datasets from 52 epidemiological studies were analysed centrally. The principal analyses involved the prospective studies (with last hormone therapy use extrapolated forwards for up to 4 years). Sensitivity analyses included the retrospective studies. Adjusted Poisson regressions yielded relative risks (RRs) versus never-use. Findings During prospective follow-up, 12 110 postmenopausal women, 55% (6601) of whom had used hormone therapy, developed ovarian cancer. Among women last recorded as current users, risk was increased even with <5 years of use (RR 1.43, 95% CI 1.31-1.56; p<0.0001). Combining current-or-recent use (any duration, but stopped <5 years before diagnosis) resulted in an RR of 1.37 (95% CI 1.29-1.46; p<0.0001); this risk was similar in European and American prospective studies and for oestrogen-only and oestrogen-progestagen preparations, but differed across the four main tumour types (heterogeneity p<0.0001), being definitely increased only for the two most common types, serous (RR 1.53, 95% CI 1.40-1.66; p<0.0001) and endometrioid (1.42, 1.20-1.67; p<0.0001). Risk declined the longer ago use had ceased, although about 10 years after stopping long-duration hormone therapy use there was still an excess of serous or endometrioid tumours (RR 1.25, 95% CI 1.07-1.46, p=0.005). Interpretation The increased risk may well be largely or wholly causal; if it is, women who use hormone therapy for 5 years from around age 50 years have about one extra ovarian cancer per 1000 users and, if its prognosis is typical, about one extra ovarian cancer death per 1700 users.
  • Lawrenson, Kate, et al. (författare)
  • Functional mechanisms underlying pleiotropic risk alleles at the 19p13.1 breast-ovarian cancer susceptibility locus
  • 2016
  • Ingår i: Nature Communications. - Nature Publishing Group. - 2041-1723. ; 7
  • Tidskriftsartikel (refereegranskat)abstract
    • A locus at 19p13 is associated with breast cancer (BC) and ovarian cancer (OC) risk. Here we analyse 438 SNPs in this region in 46,451 BC and 15,438 OC cases, 15,252 BRCA1 mutation carriers and 73,444 controls and identify 13 candidate causal SNPs associated with serous OC (P=9.2 × 10−20), ER-negative BC (P=1.1 × 10−13), BRCA1-associated BC (P=7.7 × 10−16) and triple negative BC (P-diff=2 × 10−5). Genotype-gene expression associations are identified for candidate target genes ANKLE1 (P=2 × 10−3) and ABHD8 (P<2 × 10−3). Chromosome conformation capture identifies interactions between four candidate SNPs and ABHD8, and luciferase assays indicate six risk alleles increased transactivation of the ADHD8 promoter. Targeted deletion of a region containing risk SNP rs56069439 in a putative enhancer induces ANKLE1 downregulation; and mRNA stability assays indicate functional effects for an ANKLE1 3′-UTR SNP. Altogether, these data suggest that multiple SNPs at 19p13 regulate ABHD8 and perhaps ANKLE1 expression, and indicate common mechanisms underlying breast and ovarian cancer risk.
  • Dillner, Joakim, et al. (författare)
  • Four year efficacy of prophylactic human papillomavirus quadrivalent vaccine against low grade cervical, vulvar, and vaginal intraepithelial neoplasia and anogenital warts: randomised controlled trial.
  • 2010
  • Ingår i: BMJ (Clinical research ed.). - 1468-5833. ; 341, s. c3493
  • Tidskriftsartikel (refereegranskat)abstract
    • OBJECTIVES: To evaluate the prophylactic efficacy of the human papillomavirus (HPV) quadrivalent vaccine in preventing low grade cervical, vulvar, and vaginal intraepithelial neoplasias and anogenital warts (condyloma acuminata). DESIGN: Data from two international, double blind, placebo controlled, randomised efficacy trials of quadrivalent HPV vaccine (protocol 013 (FUTURE I) and protocol 015 (FUTURE II)). The trials were to be 4 years in length, and the results reported are from final study data of 42 months' follow-up. SETTING: Primary care centres and university or hospital associated health centres in 24 countries and territories around the world. PARTICIPANTS: 17 622 women aged 16-26 years enrolled between December 2001 and May 2003. Major exclusion criteria were lifetime number of sexual partners (>4), history of abnormal cervical smear test results, and pregnancy. INTERVENTION: Three doses of quadrivalent HPV vaccine (for serotypes 6, 11, 16, and 18) or placebo at day 1, month 2, and month 6. MAIN OUTCOME MEASURES: Vaccine efficacy against cervical, vulvar, and vaginal intraepithelial neoplasia grade I and condyloma in a per protocol susceptible population that included subjects who received all three vaccine doses, tested negative for the relevant vaccine HPV types at day 1 and remained negative through month 7, and had no major protocol violations. Intention to treat, generally HPV naive, and unrestricted susceptible populations were also studied. RESULTS: In the per protocol susceptible population, vaccine efficacy against lesions related to the HPV types in the vaccine was 96% for cervical intraepithelial neoplasia grade I (95% confidence interval 91% to 98%), 100% for both vulvar and vaginal intraepithelial neoplasia grade I (95% CIs 74% to 100%, 64% to 100% respectively), and 99% for condyloma (96% to 100%). Vaccine efficacy against any lesion (regardless of HPV type) in the generally naive population was 30% (17% to 41%), 75% (22% to 94%), and 48% (10% to 71%) for cervical, vulvar, and vaginal intraepithelial neoplasia grade I, respectively, and 83% (74% to 89%) for condyloma. CONCLUSIONS: Quadrivalent HPV vaccine provided sustained protection against low grade lesions attributable to vaccine HPV types (6, 11, 16, and 18) and a substantial reduction in the burden of these diseases through 42 months of follow-up. TRIAL REGISTRATIONS: NCT00092521 and NCT00092534.
  • Paavonen, J, et al. (författare)
  • Baseline demographic characteristics of subjects enrolled in international quadrivalent HPV (types 6/11/16/18) vaccine clinical trials
  • 2008
  • Ingår i: Current Medical Research and Opinion. - Informa Healthcare. - 1473-4877 .- 0300-7995. ; 24:6, s. 1623-1634
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND: In Phase II/III trials, administration of quadrivalent human papillomavirus (HPV) (types 6/11/16/18) L1 virus-like-particle vaccine was highly effective in preventing HPV6/11/16/18-related cervical intraepithelial neoplasia and non-invasive cervical cancer in women aged 16-26 years who were naïve to these HPV types at enrollment. However, the makeup and extent of catch-up vaccination programs among young women is unclear, because a proportion of this population will likely already have been exposed to one or more vaccine-HPV-types.<br /> &lt;br&gt;<br /> OBJECTIVE: Herein we analyze baseline data from the quadrivalent HPV vaccine clinical trial program to investigate variables which may help shape catch-up vaccine implementation policies.<br /> &lt;br&gt;<br /> METHODS: Female adolescents and young adults aged 16-26 years were randomized into five clinical trials. Baseline data regarding demographics, sexual history, pregnancy history, and other characteristics were collected at enrollment. At the baseline gynecological examination during enrollment, specimens were obtained for Pap testing. Swabs of external genital, lateral vaginal, and cervical sites for HPV polymerase chain reaction (PCR) testing were taken, and serum samples were obtained for HPV serology testing. Regional analyses of data were conducted.<br /> &lt;br&gt;<br /> RESULTS: Overall, 72% of subjects enrolled worldwide were naïve by both serology and PCR to all four vaccine HPV types. Few subjects were seropositive and/or PCR positive for more than two vaccine-related HPV types. Of all subjects with HSIL at enrollment, 78% were positive to at least one vaccine-related HPV type at enrollment. Regional differences in HPV and STD prevalence were evident. Study limitations included under-representation of women with &gt;/=4 sexual partners and possible underestimation of prior HPV exposure.<br /> &lt;br&gt;<br /> CONCLUSIONS: Our findings demonstrate that sexually active 16-26 year-old women with &lt;/=4 life time sex partners (LSP) in North America, Europe, Latin America, and Asia Pacific are generally naïve to most or all types targeted by the quadrivalent HPV6/11/16/18 vaccine and that they are at subsequent risk for infection and disease caused by these types.
  • Nygård, Mari, et al. (författare)
  • Targeting human papillomavirus to reduce the burden of cervical, vulvar and vaginal cancer and pre-invasive neoplasia: establishing the baseline for surveillance.
  • 2014
  • Ingår i: PLOS One. - Public Library of Science. - 1932-6203. ; 9:2, s. e88323
  • Tidskriftsartikel (refereegranskat)abstract
    • Infection with high-risk human papillomavirus (HPV) is causally related to cervical, vulvar and vaginal pre-invasive neoplasias and cancers. Highly effective vaccines against HPV types 16/18 have been available since 2006, and are currently used in many countries in combination with cervical cancer screening to control the burden of cervical cancer. We estimated the overall and age-specific incidence rate (IR) of cervical, vulvar and vaginal cancer and pre-invasive neoplasia in Denmark, Iceland, Norway and Sweden in 2004-2006, prior to the availability of HPV vaccines, in order to establish a baseline for surveillance. We also estimated the population attributable fraction to determine roughly the expected effect of HPV16/18 vaccination on the incidence of these diseases.
  • Canton, Sophie, et al. (författare)
  • Visualizing the non-equilibrium dynamics of photoinduced intramolecular electron transfer with femtosecond X-ray pulses.
  • 2015
  • Ingår i: Nature Communications. - Nature Publishing Group. - 2041-1723. ; 6, s. 6359
  • Tidskriftsartikel (refereegranskat)abstract
    • Ultrafast photoinduced electron transfer preceding energy equilibration still poses many experimental and conceptual challenges to the optimization of photoconversion since an atomic-scale description has so far been beyond reach. Here we combine femtosecond transient optical absorption spectroscopy with ultrafast X-ray emission spectroscopy and diffuse X-ray scattering at the SACLA facility to track the non-equilibrated electronic and structural dynamics within a bimetallic donor-acceptor complex that contains an optically dark centre. Exploiting the 100-fold increase in temporal resolution as compared with storage ring facilities, these measurements constitute the first X-ray-based visualization of a non-equilibrated intramolecular electron transfer process over large interatomic distances. Experimental and theoretical results establish that mediation through electronically excited molecular states is a key mechanistic feature. The present study demonstrates the extensive potential of femtosecond X-ray techniques as diagnostics of non-adiabatic electron transfer processes in synthetic and biological systems, and some directions for future studies, are outlined.
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