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The possibility of extending the microscopic e-decay theory to exotic decay modes is investigated. It is argued that the strong Pauli distortions in the antisymmetrized wave function of the open channel favour this possibility. The microscopic description can be reduced to a onebody picture; the structure information is then contained in a spectroscopic factor. Existing microscopic calculations from ~-up to 160-decays justify a simple unified bulk formula for the spectroscopic factor. In this way a semiemp]rical formula for the decay constant is obtained depending on 1 parameter only (for odd and even nuclei, respectively). This formula describes all decay modes in a unified way and yields an excellent reproduction of the known exotic decay rates. It is thus well-suited for the unambiguous prediction of yet unmeasured decay constants. PACS: 23.60. + e; 29.90. + w; 21.60.Gx

We demonstrate that a modified point diffraction interferometer can be used to measure the power distribution of different kinds of ophthalmic lenses such as spectacles, rigid and soft contact lenses, progressive lenses, etc. The relationship between the shape of the fringes and the power characteristics of the component being tested is simple and makes the design a very convenient and robust tool for inspection or quality control. Some simulations based on the Fresnel approximation are included.

SIGNIFICANCE Increasing prevalence of refractive error requires assessment of ametropia as a screening tool in children. If cycloplegia is not an option, knowledge about the increase in uncertainty for wavefront-based autorefraction is needed. The cycloplegic agent as the principal variant presents cross-reference and allows for extraction of the influence of accommodation. PURPOSE The purpose of this study was to determine the repeatability, agreement, and propensity to accommodate of cycloplegic (ARc) and noncycloplegic (ARnc) wavefront-based autorefraction (ZEISS i.Profiler plus; Carl Zeiss Vision, Aalen, Germany) in children aged 2 to 15 years. METHODS In a clinical setting, three consecutive measurements were feasible for 145 eyes (OD) under both conditions. Data are described by spherical equivalent (M), horizontal or vertical astigmatic component (J0), and oblique astigmatic component (J45). In the case of M, the most positive value of the three measurements was chosen, whereas the mean was applied for astigmatic components. RESULTS Regarding agreement, differences for ARc minus ARnc were statistically significant: for M, 0.55 (0.55 D; mean [SD]; P < .001), that is, more hyperopic in cycloplegia; for J0, −0.03 (0.11 D; P = .002); and for J45, −0.03 D (SD, 0.09 D; P < .001). Regarding repeatability, astigmatic components showed excellent repeatability: SD < 0.11 D (ARnc) and SD < 0.09 D (ARc). The repeatability of M was SD = 0.57 D with a 95% interval of 1.49 D (ARnc). Under cycloplegia, this decreased to SD = 0.17 D (ARc) with a 95% interval of 0.50 D. The mean propensity to accommodate was 0.44 D from repeated measurements; in cycloplegia, this was reduced to 0.19 D. CONCLUSIONS Wavefront-based refraction measurement results are highly repeatable and precise for astigmatic components. Noncycloplegic measurements of M show a systematic bias of 0.55 D. Cycloplegia reduces the propensity to accommodate by a factor of 2.4; for noncycloplegic repeated measurements, accommodation is controlled to a total interval of 1.49 D (95%). Without cycloplegia, results improve drastically when measurements are repeated.