We study the divergent integrals that occur in all post-Newtonian (PN) treatments of radiation reaction in slow-motion, gravitationally bound systems in general relativity. The PN methods implicitly assume that the near-zone metric has a valid asymptotic expansion in powers of the small velocity parameter E. We first show explicitly (for the gauge to be used here) that a PN-approximati03 method leads to a divergent integral at 4-PN order. This divergence arises from the second iteration. Matching arguments are then used to calculate a near-zone tern of O(lnci larger than 4-PN order. On the basis of this calculation and several previous model problems, we argue that the PN divergences signify the breakdown of the P N power-series assumptions, rather than a breakdown of the near and wave zones. Our results suggest that the P N calculations in fact give correct answers at least up to the orders at which divergences appear. The nonanalytic term of 0 (lne) beyond 4-PN order arises in the near zone via matching to the wave-zone expansion when we include terms of 0 (e3) beyond linearized order. We also solve the wave-zone equations at 0 (e6) beyond linearized order and analyze the inner expansion of the solutions. Matching gives rise to a nonanalytic term in the wave zone at O ( c l ' l n~) ,i.e., at O(c61nc) beyond linearized order. A straining technique is used in the wave-zone expansion to give a sufficiently accurate approximation to the null surfaces near past and future null infinity. The lowest-order strained solution at first appears to contribute a large, anomalous, time-odd piece to the reaction potential. However, after analyzing the contribution of higher-order wave-zone terms, we obtain agreement with the Burke reaction potential. Our results thus strongly support the usual quadrupole formula.

Purpose:To evaluate if using the Ehlers correction factor on the intraocular pressure (IOP) measured using the Goldmann applanation tonometer (GAT) improves its agreement with the PASCAL dynamic contour tonometer (DCT).Patients and methods:A total of 120 eyes of 120 individuals were examined. Participants underwent IOP measurement with both the DCT and the GAT and central corneal thickness measurement. The Ehlers correction factor was applied on the GAT IOP measurements to calculate Ehlers-corrected GAT IOP. The agreement between the DCT and GAT, and DCT and Ehlers-corrected GAT IOP was analyzed. The analyses were repeated by stratifying the data by race.Results:The mean IOP of the GAT, DCT, and the Ehlers-corrected GAT was 15.30, 16.78, and 14.68 mmHg, respectively. The agreement as assessed by Bland–Altman plot for the GAT with the DCT and DCT and Ehlers-corrected GAT IOP was +4.1 to −6.9 and +4.15 to −8.25 mmHg, respectively. The results were similar even when stratifying the data by race.Conclusion:Using Ehlers correction factor to account for the effect of corneal parameters on the IOP measured by the GAT worsens the agreement with the DCT. This effect remains even when stratifying the data by race.

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In the community screening, FDT performed reliably and identified abnormalities in a significant number of persons in the high-risk group passing the eye health part of the screening. However, with the exception of the poor sensitivity shown by strategy 4, results from the simulated screening did not support the usefulness of one strategy over another.