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PurposeProliferative vitreoretinopathy (PVR) is the most common cause of failure of surgically repaired rhegmatogenous retinal detachment (RRD). Chemically-induced and cell-injection PVR models do not fully simulate the clinical characteristics of PVR in the post-RRD context. There is an unmet need for translational models in which to study mechanisms and treatments specific to RRD-PVR.MethodsRRD-PVR was induced in adult Dutch Belted rabbits. Posterior segments of enucleated globes were fixed or processed for RNA-Seq at 6 hours and 2, 7, 14, and 35 days post-induction. Histochemical staining and immunolabeling for glial fibrillary acidic protein (GFAP), alpha smooth muscle actin (αSMA), vascular endothelial growth factor receptor 2 (VEGFR2), CD68, and retinal pigment epithelium 65 kDa protein (RPE65) were performed, and labeling intensity was scored. Single cell RNA sequencing was performed.ResultsAcute histopathologic changes included intravitreal and intraretinal hemorrhage, leukocytic vitritis, chorioretinitis, and retinal rarefaction. Chronic lesions showed retinal atrophy, gliosis, fibrotic subretinal membranes, and epiretinal fibrovascular proliferation. Fibrillar collagen was present in the fibrocellular and fibrovascular membranes in chronic lesions. Moderate to strong labeling of glia and vasculature was detected in chronic lesions. At day 14, most cells profiled by single cell sequencing were identified as Müller glia and microglia, consistent with immunolabeling. Expression of several fibrillar collagen genes were upregulated in chronic lesions.ConclusionsHistologic and transcriptional features of this rabbit model simulate important features of human RRD-PVR, including the transition to chronic intra and periretinal fibrosis. This high-fidelityin vivomodel of RRD-PVR will enable further research on targeted treatment interventions.

The decay of the 21.47-MeV stretched resonance in $^{13}$C, arising from p3/2→d5/2 nucleon excitation coupled to maximum spin, was investigated in a (p,p′) experiment at 135 MeV proton bombarding energy, performed at the Cyclotron Centre Bronowice (CCB) at IFJ PAN in Krakow. First experimental information on the proton and neutron decay branches from this state was obtained by using coincidence measurement of protons inelastically scattered on a $^{13}$C target and γ rays from daughter nuclei, namely, $^{12}$B (proton decay) and $^{12}$C (neutron decay). The main branches lead to the Jπ=2+, first-excited state at 0.953 MeV in $^{12}$B, and to the Jπ=1+, T=1 level at 15.110 MeV in $^{12}$C. The results were compared with predictions from the Gamow Shell Model (GSM), which was used to describe the stretched resonance in terms of its energy, width, electromagnetic transition strengths and decay pattern. A very good agreement was obtained between the measured and calculated properties of the 21.47-MeV stretched resonance in $^{13}$C, demonstrating the high-quality and precision of the GSM wave function calculations, which include coupling to the resonant and non-resonant particle continuum.

Submarine groundwater discharge is increasingly recognized as an important component of the oceanic geochemical budget, but knowledge of the distribution of this phenomenon is limited. To date, reports of meteoric inputs to marine sediments are typically limited to shallow shelf and coastal environments, whereas contributions of freshwater along deeper sections of tectonically active margins have generally been attributed to silicate diagenesis, mineral dehydration, or methane hydrate dissociation. Here, using geochemical fingerprinting of pore water data from Site J1003 recovered from the Chilean Margin during D/V JOIDES Resolution Expedition 379 T, we show that substantial offshore freshening reflects deep and focused contributions of meteorically modified geothermal groundwater, which is likely sourced from a reservoir ~2.8 km deep in the Aysén region of Patagonia and infiltrated marine sediments during or shortly after the last glacial period. Emplacement of fossil groundwaters reflects an apparently ubiquitous phenomenon in margin sediments globally, but our results now identify an unappreciated locus of deep submarine groundwater discharge along active margins with potential implications for coastal biogeochemical processes and tectonic instability.

Human retinal organoid transplantation can potentially restore vision in patients with degenerative retinal diseases. How the recipient retina regulates the maturation, fate specification, and migration of transplanted organoid cells is unknown. We transplanted human retinal organoid-derived cells into photoreceptor-deficient mice, conducted histology and single-cell RNA sequencing analyses, and observed two main classes of graft-derived cells. The first class consisted of retinal astrocytes and brain/spinal cord-like neural precursors, absent or rare in cultured organoids, that migrated into all recipient retinal layers and traveled long distances. The second class consisted of retinal progenitor-derived cells, including rods and cones, that remained in the subretinal space and matured more rapidly than photoreceptors in culture. These data suggest that the recipient subretinal space promotes the maturation of transplanted photoreceptors while inducing or expanding migratory cell populations that are not normally derived from retinal progenitors. These findings have important implications for cell-based treatment of retinal diseases.

A new measurement of γ decay from the states above the neutron threshold in Pb208 has been performed at Cyclotron Centre Bronowice in Kraków, Poland. The main goal of the experiment was to observe the γ decay to the ground state from the isoscalar giant quadrupole resonance (ISGQR). To this day, the only published observation of this phenomenon dates back to the late 1980s, where γ decay to the ground state branching ratio was reported. At variance with the existing measurement using inelastic scattering of O17, here proton inelastic scattering is employed. In particular, data were obtained for Pb208(p,p′γ) at 85 MeV beam energy, where γ rays were measured for proton scattering angles 8.9∘, 10.7∘, 12.5∘, and 14.3∘. By applying a similar analysis method as in the previous experiment, the branching ratio of ISGQR gamma decay to the ground state was extracted from the data.

This chapter foregrounds an online gamified visual intelligence innovation (eyebraingym) developed to enhance visual processing skills, improve memory and vocabulary, and increase reading fluency. The explicit aim of the innovation is to improve comprehension towards visual intelligence. Ninety-eight Grade 8 learners at a South African Boy's School completed their online development during the 2021 academic year. These learners were part of a group of students participating in a whole school reading and literacy intervention program. The innovation is an integral part of this ongoing project. Their interaction with the innovation consists of 15 sessions completed once or twice a week for 20 – 40 minutes over five months. The results of the project are positive. It shows that most participating students improved their perceptual development and reading speed (VPF) and cognitive development and comprehension skills (CDF). In addition, these outcomes transferred to improved relative efficiency when working with information (AIUF).

Sediment cores recently collected from the Chilean Margin during D/V JOIDES Resolution Expedition 379T (JR100) document variability in shipboard-generated records of the green/blue (G/B) ratio. These changes show a strong coherence with benthic foraminiferal δ18O, Antarctic ice core records, and sediment lithology (e.g., higher diatom abundances in greener sediment intervals), suggesting a climate-related control on the G/B. Here, we test the utility of G/B as a proxy for diatom productivity at Sites J1002 and J1007 by calibrating G/B to measured biogenic opal. Strong exponential correlations between measured opal% and the G/B were found at both sites. We use the empirical regressions to generate high-resolution records of opal contents (opal%) on the Chilean Margin. Higher productivity tends to result in more reducing sedimentary conditions. Redox-sensitive sedimentary U/Th generally co-varies with the reconstructed opal% at both sites, supporting the association between sediment color, sedimentary U/Th, and productivity. Lastly, we calculated opal mass accumulation rate (MAR) at Site J1007 over the last ∼150,000 years. The G/B-derived opal MAR record from Site J1007 largely tracks existing records derived from traditional wet-alkaline digestion from the south and eastern equatorial Pacific (EEP) Ocean, with a common opal flux peak at ∼50 ka suggesting that increased diatom productivity in the EEP was likely driven by enhanced nutrient supply from the Southern Ocean rather than dust inputs as previously suggested. Collectively, our results identify the G/B ratio as a useful tool with the potential to generate reliable, high-resolution paleoceanographic records that circumvent the traditionally laborious methodology. publishedVersion

High-resolution -ray spectroscopy of is performed with the Advanced GAmma Tracking Array, following deep-inelastic processes induced by an beam on a target. Six states are newly identified, which together with the three known excitations exhaust all negative-parity excited states expected in below the neutron threshold. Spin and parities are proposed for all located states on the basis of decay branchings and comparison with large-scale shell-model calculations performed in the p-sd space, with the YSOX interaction. Of particular interest is the location of the and excitations, which provide strong constrains for cross-shell p-sd matrix elements based on realistic interactions and help to simultaneously reproduce the ground and first-excited states in and , for the first time. Understanding the structure may also have significant impact on neutron-capture cross-section calculations in r-process modeling including light neutron-rich nuclei.

International audience; A recent extension of the Doppler-shift attenuation method to measure short lifetimes of states populated in low-energy binary reactions is applied to the case of 17N. The reliability of the technique is confirmed by measuring the lifetime of the 5515 keV 3/2− state, which is depopulated by two different γ rays. The method is used to measure the lifetime of the 5170 keV (9/2+) state in the same nucleus. Comparisons with large-scale shell-model predictions are given as well.

OBJECTIVES: Cone photoreceptor transplantation is a potential treatment for macular diseases. The optimal conditions for cone transplantation are poorly understood, partly because of the scarcity of cones in donor mice. To facilitate allogeneic cone photoreceptor transplantation studies in mice, we aimed to create and characterize a donor mouse model containing a cone-rich retina with a cone-specific enhanced green fluorescent protein (EGFP) reporter. METHODS: We generated OPN1LW-EGFP/NRL(−/−) mice by crossing NRL(−/−) and OPN1LW-EGFP mice. We characterized the anatomical phenotype of OPN1LW-EGFP/NRL(−/−) mice using multimodal confocal scanning laser ophthalmoscopy (cSLO) imaging, immunohistology, and transmission electron microscopy. We evaluated retinal function using electroretinogram (ERG), including 465 and 525 nm chromatic stimuli. Retinal sheets and cell suspensions from OPN1LW-EGFP/NRL(−/−) mice were transplanted subretinally into immunodeficient Rd1 mice. RESULTS: OPN1LW-EGFP/NRL(−/−) retinas were enriched with OPN1LW-EGFP(+) and S-opsin(+) cone photoreceptors in a dorsal-ventral distribution gradient. Cone photoreceptors co-expressing OPNL1W-EGFP and S-opsin significantly increased in OPN1LW-EGFP/NRL(−/−) compared to OPN1LW-EGFP mice. Temporal dynamics of rosette formation in the OPN1LW-EGFP/NRL(−/−) were similar as the NRL(−/−) with peak formation at P15. Rosettes formed preferentially in the ventral retina. The outer retina in P35 OPN1LW-EGFP/NRL(−/−) was thinner than NRL(−/−) controls. The OPN1LW-EGFP/NRL(−/−) ERG response amplitudes to 465 nm stimulation were similar to, but to 535 nm stimulation were lower than, NRL(−/−) controls. Three months after transplantation, the suspension grafts showed greater macroscopic degradation than sheet grafts. Retinal sheet grafts from OPN1LW-EGFP/NRL(−/−) mice showed greater S-opsin+ cone survival than suspension grafts from the same strain. CONCLUSIONS: OPN1LW-EGFP/NRL(−/−) retinae were enriched with S-opsin(+) photoreceptors. Sustained expression of EGFP facilitated the longitudinal tracking of transplanted donor cells. Transplantation of cone-rich retinal grafts harvested prior to peak rosette formation survived and differentiated into cone photoreceptor subtypes. Photoreceptor sheet transplantation may promote greater macroscopic graft integrity and S-opsin(+) cone survival than cell suspension transplantation, although the mechanism underlying this observation is unclear at present. This novel cone-rich reporter mouse strain may be useful to study the influence of graft structure on cone survival.

To test the predictive power of ab initio nuclear structure theory, the lifetime of the second 2+ state in neutron-rich O20,τ(22+)=150-30+80fs, and an estimate for the lifetime of the second 2+ state in C16 have been obtained for the first time. The results were achieved via a novel Monte Carlo technique that allowed us to measure nuclear state lifetimes in the tens-to-hundreds of femtoseconds range by analyzing the Doppler-shifted γ-transition line shapes of products of low-energy transfer and deep-inelastic processes in the reaction O18(7.0MeV/u)+Ta181. The requested sensitivity could only be reached owing to the excellent performances of the Advanced γ-Tracking Array AGATA, coupled to the PARIS scintillator array and to the VAMOS++ magnetic spectrometer. The experimental lifetimes agree with predictions of ab initio calculations using two-and three-nucleon interactions, obtained with the valence-space in-medium similarity renormalization group for O20 and with the no-core shell model for C16. The present measurement shows the power of electromagnetic observables, determined with high-precision γ spectroscopy, to assess the quality of first-principles nuclear structure calculations, complementing common benchmarks based on nuclear energies. The proposed experimental approach will be essential for short lifetime measurements in unexplored regions of the nuclear chart, including r-process nuclei, when intense beams, produced by Isotope Separation On-Line (ISOL) techniques, become available.

International audience; The electromagnetic structure of Zn66 at low excitation energy was investigated via low-energy Coulomb excitation at INFN Legnaro National Laboratories, using the Gamma Array of Legnaro Infn Laboratories for nuclEar spectrOscopy (GALILEO) γ-ray spectrometer coupled to the SPIDER (Silicon PIe DEtectoR). A set of reduced E2, E3, and M1 matrix elements was extracted from the collected data using the gosia code, yielding 12 reduced transition probabilities between the low-spin states and the spectroscopic quadrupole moment of the 21+ state. The B(E2) values for transitions depopulating the 02+ state have been determined for the first time, allowing for the lifetime of this state to be deduced and, consequently, the ρ2(E0;02+→01+) monopole transition strength to be extracted. In addition, the B(E3;31−→01+) value has been determined for the first time in a Coulomb excitation experiment. The obtained results resolve the existing discrepancies between literature lifetimes and demonstrate that Zn66 cannot be described by using simple collective models. Therefore, new state-of-the-art beyond-mean-field and large-scale shell-model calculations were performed in order to interpret the structure of this nucleus. Both the experimental and theoretical results suggest that the triaxial degree of freedom has an important impact on electromagnetic properties of Zn66, while the unique features of the 02+ state indicate its distinct and rather isolated structure.

International audience; High-resolution γ-ray spectroscopy of N18 is performed with the Advanced GAmma Tracking Array, following deep-inelastic processes induced by an O18 beam on a Ta181 target. Six states are newly identified, which together with the three known excitations exhaust all negative-parity excited states expected in N18 below the neutron threshold. Spin and parities are proposed for all located states on the basis of decay branchings and comparison with large-scale shell-model calculations performed in the p-sd space, with the YSOX interaction. Of particular interest is the location of the 01− and 12− excitations, which provide strong constrains for cross-shell p-sd matrix elements based on realistic interactions and help to simultaneously reproduce the ground and first-excited states in N16 and N18, for the first time. Understanding the N18 structure may also have significant impact on neutron-capture cross-section calculations in r-process modeling including light neutron-rich nuclei.

Geoscience graduate programs are increasingly abandoning the controversial test as an admissions requirement, a welcome development for equity and inclusion in the field. How can your school be next?