The evolutions of the flat FLRW universe and its linear perturbations are studied systematically in the dressed metric approach of LQC. When it is dominated by the kinetic energy of the inflaton at the quantum bounce, the evolution of the background can be divided into three different phases prior to the preheating, {\em bouncing, transition and slow-roll inflation}. During the bouncing phase, the evolution is independent of not only the initial conditions, but also the inflationary potentials. In particular, the expansion factor can be well described by the same exact solution in all the cases considered. In contrast, in the potential dominated case such a universality is lost. It is because of this universality that the linear perturbations are also independent of the inflationary models and obtained exactly. During the transition phase, the evolutions of the background and its linear perturbations are found explicitly, and then matched to the ones given in the other two phases. Hence, once the initial conditions are imposed, the linear scalar and tensor perturbations will be uniquely determined. Considering two different sets of initial conditions, one imposed during the contracting phase and the other at the bounce, we calculate the Bogoliubov coefficients and find that the two sets yield the same results and all lead to particle creations at the onset of the inflation. Due to the pre-inflationary dynamics, the scalar and tensor power spectra become scale-dependent. Comparing with the Planck 2015 data, we find constraints on the total e-folds that the universe must have expanded since the bounce, in order to be consistent with current observations.Comment: revtex4, 23 figures, and 5 tables. Some typos were corrected. Phys. Rev. D 96, 083520 (2017

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Background The European Randomized Study of Screening for Prostate Cancer (ERSPC) found screening reduced prostate cancer (PC) mortality, but the Prostate, Lung, Colorectal, and Ovarian trial (PLCO) found no reduction. Objective To evaluate whether effects of screening on PC mortality relative to no screening differed between the ERSPC and PLCO. Design Cox regression of PC death in each trial arm adjusted for age and trial, and extended analyses that accounted for increased incidence due to screening and diagnostic workup on each arm via mean lead times (MLTs). MLTs were estimated empirically and using analytic or microsimulation models. Setting Randomized controlled trials in Europe and the US. Participants Men aged 55–69 (ERSPC) or 55–74 (PLCO) at randomization. Intervention Prostate cancer screening. Measurements PC incidence and survival from randomization; PC incidence in the US before screening began. Results Estimated MLTs were similar in the ERSPC and PLCO intervention arms but were longer in the PLCO control arm than the ERSPC control arm. Extended analyses found no evidence that effects of screening differed between trials (P=0.37–0.47, range across MLT estimation approaches) but strong evidence that benefit increased with MLT (P=0.0027–0.0032). Screening was estimated to confer a 7–9% reduction in PC death per year of MLT. This translated into an estimated 25–31% and 27–32% lower risk of PC death under screening as performed in the ERSPC and PLCO intervention arms, respectively, relative to no screening. Limitations MLT is a simple metric of screening and diagnostic workup. Conclusion After accounting for differences in implementation and settings, the ERSPC and PLCO provide compatible evidence that screening reduces PC mortality.