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Purpose : Brain abnormalities have been associated with glaucoma, which damages the ganglion cell complex (GCC). In this study, we will directly associate the GCC thickness with brain parameters in subjects without glaucoma. Methods : From the large population-based LIFE-Adult study (Leipzig Research Centre for Civilization Diseases), we extracted the machine-segmented GCC thickness from macular optical coherence tomography (SD-OCT) scans. We applied an artificial intelligence method termed non-negative matrix factorization to determine GCC thickness patterns. The brain parameters used include left and right hippocampal volumes, white matter volume and white matter hyperintensity volume, which were measured using automatic segmentation tools (FreeSurfer and LesionTOADS) on magnetic resonance imaging scans. The global average GCC thickness and each of the GCC thickness patterns were associated with the brain parameters by linear regression with adjusted effects for age, gender, scan focus and intracranial volume. P values were corrected for multiple comparisons for the GCC thickness patterns by the false discovery rate method. For linear regression analyses, subjects with glaucoma diagnosis were excluded and one random eye per subject was selected if data for both eyes were available. Results : We determined 12 GCC thickness patterns (Figure 1) using 17,877 OCT scans from 17,877 eyes of 9,029 subjects (Age: 57.5 ± 12.4 years, 52.1% female). The brighter regions in the GCC thickness patterns indicate the more informative zones with greater variations across subjects than the blue regions. 1,747 eyes from 1,747 subjects (Age: 58.2 ± 15.8 years, 45.6% female) were used to link the GCC parameters with the brain parameters. The global average GCC thickness was not significantly associated with any of the brain parameters (Table 1). A lower Pattern 3 coefficient was correlated with lower left (p < 0.001) and right (p = 0.006) hippocampal volumes. A lower Pattern 5 coefficient was correlated with lower right hippocampal volume and higher white matter hyperintensity volume (p = 0.04 for both). A lower Pattern 5 coefficient was also correlated with lower white matter volume with borderline significance (p = 0.07; p = 0.005 before p value corrections). Conclusions : Our results suggest that parafovea ring-shape thinning and inferior-nasal arcuate-shape thinning in GCC are specifically linked with unfavorable brain parameters. This is a 2021 Imaging in the Eye Conference abstract.

Precis: In open-angle glaucoma, when neuroretinal rim tissue measured by volumetric optical coherence tomography (OCT) scans is below a third of the normal value, visual field (VF) damage becomes detectable. Purpose: To determine the amount of neuroretinal rim tissue thickness below which VF damage becomes detectable. Methods: In a retrospective cross-sectional study, 1 eye per subject (of 57 healthy and 100 open-angle glaucoma patients) at an academic institution had eye examinations, VF testing, spectral-domain OCT retinal nerve fiber layer (RNFL) thickness measurements, and optic nerve volumetric scans. Using custom algorithms, the minimum distance band (MDB) neuroretinal rim thickness was calculated from optic nerve scans. "Broken-stick" regression was performed for estimating both the MDB and RNFL thickness tipping-point thresholds, below which were associated with initial VF defects in the decibel scale. The slopes for the structure-function relationship above and below the thresholds were computed. Smoothing curves of the MDB and RNFL thickness covariates were evaluated to examine the consistency of the independently identified tipping-point pairs. Results: Plots of VF total deviation against MDB thickness revealed plateaus of VF total deviation unrelated to MDB thickness. Below the thresholds, VF total deviation decreased with MDB thickness, with the associated slopes significantly greater than those above the thresholds (P

After four years, eight Presidency terms and numerous Presidency compromise proposals that followed the Commission’s initial proposal,1 on 27 June 2016 the European Council adopted a Directive to h...

Dipole strength distributions measured in unstable neutron-rich nuclei in the Sn-132 mass region by utilizing relativistic Coulomb excitation of radioactive beams reveal a sizable fraction of "pygmy" strength below the giant dipole resonance. On the grounds of the RQRPA model, a strong linear correlation between the pygmy strength, parameters of the nuclear symmetry energy and the neutron skin thickness has been found. From the experimentally observed low-lying strength, the symmetry energy pressure p(0) = 2.3 +/- 0.8 MeV/fm(3) and neutron skin thicknesses of 0.23 +/- 0.04 fm Sn-130 and 0.24 +/- 0.04 fm Sn-130 have been extracted.

A concentration of dipole strength at energies below the giant dipole resonance was observed in neutron-rich nuclei around 132Sn in an experiment using the FRS-LAND setup. This so-called “pygmy” dipole strength can be related to the parameters of the symmetry energy and to the neutron skin thickness on the grounds of a relativistic quasiparticle random-phase approximation. Using this ansatz and the experimental findings for 130Sn and 132Sn, we derive a value of the symmetry energy pressure of p-bar0 = 2.2±0.5 MeV/fm3. Neutron skin thicknesses of Rn−Rp = 0.23±0.03 fm and 0.24±0.03 fm for 130Sn and 132Sn, respectively, have been determined. Preliminary results on 68Ni from a similar experiment using an improved setup indicate an enhanced cross section at low energies, while the results for 58Ni are in accordance with results from photoabsorption measurements.

The excitation of the double-phonon giant dipole resonance was observed in heavy projectile nuclei impinging on targets of high nuclear charge with energies of 500-700 MeV/nucleon. New experimental data are presented for sup 1 sup 3 sup 6 Xe and sup 2 sup 3 sup 8 U together with further analysis of earlier data on sup 2 sup 0 sup 8 Pb. Differential cross sections d sigma/dE sup * and d sigma/d theta for electromagnetic excitations were deduced. Depending on the isotope, cross sections appear to be enhanced in comparison to those expected from a purely harmonic nuclear dipole response. The cumulative effect of excitations of two-phonon states composed of one dipole and one quadrupole phonon, of predicted anharmoniticies in the double-phonon dipole response, and of damping of the dipole resonance during the collision may account for the discrepancy. In addition, decay properties of two-phonon resonances were studied and compared to that of a statistical decay.

The unbound hydrogen isotopes sup 4 sup , sup 5 H have been studied in the one-proton knockout channel of sup 6 He (240 MeV/u) impinging on a carbon target. The triton fragments originating from this channel were detected in coincidence with neutrons. Relative energy spectra as well as energy and angular correlations have been studied for the t+n and t+n+n systems. The analysis of the energy and angular correlations by the method of hyperspherical harmonic expansion allows to determine the relative weights of the most relevant partial waves in the three-body t+n+n final state. It is shown that the neutrons to a large extent occupy the p-shell and that the I suppi = 1/2 sup + state is strongly populated as expected for the sup 5 H ground state. No evidence for a narrow resonance in the t+n+n system is obtained, instead a broad structure peaked at 3 MeV above the threshold with about 6 MeV as a full width at half maximum is observed. The two-body t+n system reveals a resonance compatible with earlier results for sup 4 H.

Electromagnetic and nuclear inelastic scattering of the halo nucleus sup 1 sup 1 Be have been investigated by a measurement of the one-neutron removal channel, utilizing a secondary sup 1 sup 1 Be beam with an energy of 520 MeV/nucleon impinging on lead and carbon targets. All decay products, i.e. sup 1 sup 0 Be fragments, neutrons, and gamma-rays have been detected in coincidence. Partial cross sections for the population of ground and excited states in sup 1 sup 0 Be were determined for nuclear diffractive breakup as well as for electromagnetically induced breakup. The partial cross sections for ground-state transitions have been differentiated further with respect to excitation energy, and the dipole-strength function associated solely with transitions of the halo 2s sub 1 sub / sub 2 neutron to the continuum has been derived. The extracted dipole strength integrated from the neutron threshold up to 6.1 MeV excitation energy amounts to 0.90(6) e sup 2 fm sup 2. A spectroscopic factor for the nu 2s sub 1 sub / sub 2 x sup 1 sup 0 Be(0 sup +) single-particle configuration of 0.61(5) and a root-mean-square radius of the 2s sub 1 sub / sub 2 neutron wave function of 5.7(4) fm have been deduced.