Breast cancer risk in male twins: joint analyses of four twin cohorts in Denmark, Finland, Sweden and the United States

To test the hypothesis that in utero exposure to high levels of oestrogen increases the risk of male breast cancer, we followed 115 235 male twins for more than 3.5 million person-years at risk. We observed 11 cases of male breast cancer versus 16.16 expected based on national rates (standardized rate ratio 0.68, 95% confidence interval 0.34–1.22) and conclude that any adverse influence of in utero oestrogen exposure is likely to be small. © 2000 Cancer Research Campaig

Pushing the online matrix-vector conjecture off-line and identifying its easy cases

© Springer Nature Switzerland AG 2019. Henzinger et al. posed the so called Online Boolean Matrix-vector Multiplication (OMv) conjecture and showed that it implies tight hardness results for several basic partially dynamic or dynamic problems [STOC’15]. We show that the OMv conjecture is implied by a simple off-line conjecture. If a not uniform (i.e., it might be different for different matrices) polynomial-time preprocessing of the matrix in the OMv conjecture is allowed then we can show such a variant of the OMv conjecture to be equivalent to our off-line conjecture. On the other hand, we show that the OMV conjecture does not hold in the restricted cases when the rows of the matrix or the input vectors are clustered

Medically certified sickness absence with insurance benefits in women with and without children

Background: Sickness absence in Sweden is high, particularly in young women and the reasons are unclear. Many Swedish women combine parenthood and work and are facing demands that may contribute to impaired health and well-being. We compared mothers and women without children under different conditions, assuming increased sickness absence in mothers, due to time-based stress and psychological strain. Methods: All women born in 1960–79 (1.2 million) were followed from 1993 to 2003. Information on children in the home for each year was related to medically certified sickness absence with insurance benefits the year after. We used age and time-stratified proportional hazard regression models accounting for the individual's changes on study variables over time. Data were retrieved from national administrative registers. Results: Sickness absence was higher in mothers than in women without children, the relative risks decreased by age, with no effect after the age of 35 years. An effect appeared in lonely women irrespective of age, while in cohabiting women only for the ages 20–25 years. Mothers showed increased sickness absence in all subgroups of country of birth, education, income, sector of employment and place of residence. The relation between number of children and sickness absence was nonlinear, with the highest relative risks for mothers of one child. The upward trend of sickness absence at the end of 1990s was steeper for mothers compared to women without children. Conclusion: Despite the well-developed social security system and child care services in Sweden, parenthood predicts increased sickness absence, particularly in young and in lone women

Search for squarks and gluinos in events with isolated leptons, jets and missing transverse momentum at s√=8 TeV with the ATLAS detector

The results of a search for supersymmetry in final states containing at least one isolated lepton (electron or muon), jets and large missing transverse momentum with the ATLAS detector at the Large Hadron Collider are reported. The search is based on proton-proton collision data at a centre-of-mass energy s√=8 TeV collected in 2012, corresponding to an integrated luminosity of 20 fb−1. No significant excess above the Standard Model expectation is observed. Limits are set on supersymmetric particle masses for various supersymmetric models. Depending on the model, the search excludes gluino masses up to 1.32 TeV and squark masses up to 840 GeV. Limits are also set on the parameters of a minimal universal extra dimension model, excluding a compactification radius of 1/R c = 950 GeV for a cut-off scale times radius (ΛR c) of approximately 30