Shear Behavior of Soft Rock Exposed to Alternate Dry and Wet under Constant Stress

The surface of cutting rock slope has exposed to alternate dry and wet conditions for a long time, and they are weathered. We developed direct shear testing apparatus that can expose soft rock specimen to alternate dry and wet conditions under constant shear and normal stress, and are investigated about relationship between deformation properties and the shear behavior of soft rock under dry and wet conditions

Impact of Polyp Regression on 2-year Outcomes of Intravitreal Aflibercept Injections: A Treat-and-Extend Regimen for Polypoidal Choroidal Vasculopathy

We conducted intravitreal aflibercept injections (IVAs) for 37 Japanese patients (28 males, 9 females, mean age 73.4 years) with polypoidal choroidal vasculopathy (PCV), with a treat-and-extend regimen (TER). We evaluated the impact of polyp regression after a loading dose (2-mg IVA 1×/month for 3 months) on the patients' 2-year treatment outcomes. Thirty-seven eyes were treated with IVA by a TER for 2 years. We divided the patients into 2 groups based on their polyp status after the loading dose: polyp regression (PR+) (n=19) and no polyp regression (PR−) (n=18). We compared the groups’ best-corrected visual acuity (BCVA), central retinal thickness (CRT), recurrence rate, total number of injections, and final treatment interval. Both the BCVA and CRT were significantly improved by the treatment in both groups, with no between-group difference in the amount of change (p=0.769). In the polyp regression (+) group, recurrence was significantly less common (p=0.03), the mean total number of injections was significantly lower (p=0.013), and the mean treatment interval was significantly longer (0.042). Regarding the 2-year outcomes for PCV, the eyes with post-loading-dose polyp regression demonstrated less frequent recurrence and required fewer numbers of injections compared to the eyes without polyp regression

Results of a Treat-and-Extend Regimen of Intravitreal Ranibizumab Injection for Macular Edema due to Branch Retinal Vein Occlusion

To investigate the effectiveness of a treat-and-extend regimen (TAE) of intravitreal ranibizumab injections (IVR) for macular edema (ME) due to branch retinal vein occlusion (BRVO). We retrospectively examined 35 eyes of 35 patients with ME due to BRVO who underwent TAE for 1 year. Patients whose treatment interval extended to 12 weeks were switched to a pro re nata regimen (PRN; TAE to PRN group), while TAE was continued for patients whose treatment interval was less than 12 weeks (continued TAE group). Changes in best-corrected visual acuity (BCVA), central retinal thickness (CRT), and predictive factors for inclusion in the TAE to PRN group were analyzed. BCVA and CRT both improved significantly at 1 year compared with baseline (p<0.001). Sixteen eyes (45.7%) were included in the TAE to PRN group, while 19 eyes (54.3%) were included in the continued TAE group. BCVA in the TAE to PRN group was significantly better than that in the continued TAE group at 1 year (p=0.047). BCVA at baseline and macular BRVO were significant predictive factors for inclusion in the TAE to PRN group. TAE was effective for improving BCVA and CRT. The TAE to PRN group showed significantly better prognosis

Two-year Results of Intravitreal Ranibizumab Injections Using a Treat-and-extend Regimen for Macular Edema due to Branch Retinal Vein Occlusion

We investigated the effectiveness of a treat-and-extend regimen (TAE) of intravitreal ranibizumab injections for macular edema (ME) due to branch retinal vein occlusion (BRVO). We retrospectively examined 2-year results of 32 eyes of 32 patients who underwent TAE to treat ME due to BRVO. The patients whose treatment interval extended to ≥ 12 weeks were switched to a pro re nata regimen (PRN). For the patients whose treatment interval was <12 weeks, TAE was continued. At 2 years, 10 eyes had required no additional injections after the initial treatment period [recurrence(−) group], whereas the other 22 eyes required additional treatment [recurrence(+) group]. Among the recurrence(+) patients, 11 eyes (34.4% of total) were eventually switched from TAE to PRN; the other 11 eyes (34.4%) continued TAE for 2 years. Visual acuity and central retinal thickness were significantly improved in both the recurrence(+) and (−) groups, and there was no significant betweengroup difference in visual acuity at 2 years. Univariate analyses revealed significant differences in visual acuity (p=0.004), age (p=0.014), and vessel occlusion site (p=0.018) between these groups. Our results suggest that TAE may be effective for BRVO patients with lower visual acuity, older age, and occlusion of a major vein

Magnetized Fast Isochoric Laser Heating for Efficient Creation of Ultra-High-Energy-Density States

The quest for the inertial confinement fusion (ICF) ignition is a grand challenge, as exemplified by extraordinary large laser facilities. Fast isochoric heating of a pre-compressed plasma core with a high-intensity short-pulse laser is an attractive and alternative approach to create ultra-high-energy-density states like those found in ICF ignition sparks. This avoids the ignition quench caused by the hot spark mixing with the surrounding cold fuel, which is the crucial problem of the currently pursued ignition scheme. High-intensity lasers efficiently produce relativistic electron beams (REB). A part of the REB kinetic energy is deposited in the core, and then the heated region becomes the hot spark to trigger the ignition. However, only a small portion of the REB collides with the core because of its large divergence. Here we have demonstrated enhanced laser-to-core energy coupling with the magnetized fast isochoric heating. The method employs a kilo-tesla-level magnetic field that is applied to the transport region from the REB generation point to the core which results in guiding the REB along the magnetic field lines to the core. 7.7 $\pm$ 1.3 % of the maximum coupling was achieved even with a relatively small radial area density core ($\rho R$ $\sim$ 0.1 g/cm$^2$). The guided REB transport was clearly visualized in a pre-compressed core by using Cu-$K_\alpha$ imaging technique. A simplified model coupled with the comprehensive diagnostics yields 6.2\% of the coupling that agrees fairly with the measured coupling. This model also reveals that an ignition-scale areal density core ($\rho R$ $\sim$ 0.4 g/cm$^2$) leads to much higher laser-to-core coupling ($>$ 15%), this is much higher than that achieved by the current scheme

Hot Electron Spectra in Plain, Cone and Integrated Targets for FIREX-I using Electron Spectrometer

The traditional fast ignition scheme is that a compressed core created by an imploding laser is auxiliary heated and ignited by the hot electrons (produced by a short pulse laser guided through the cone). Here, the most suitable target design for fast ignition can be searched for by comparison of the spectra between varied targets using an electron spectrometer

Demonstration of a spherical plasma mirror for the counter-propagating kilojoule-class petawatt LFEX laser system

A counter-propagating laser-beam platform using a spherical plasma mirror was developed for the kilojoule-class petawatt LFEX laser. The temporal and spatial overlaps of the incoming and redirected beams were measured with an optical interferometer and an x-ray pinhole camera. The plasma mirror performance was evaluated by measuring fast electrons, ions, and neutrons generated in the counter-propagating laser interaction with a Cu-doped deuterated film on both sides. The reflectivity and peak intensity were estimated as ∼50% and ∼5 × 1018 W/cm2, respectively. The platform could enable studies of counter-streaming charged particles in high-energy-density plasmas for fundamental and inertial confinement fusion research.Kojima S., Abe Y., Miura E., et al. Demonstration of a spherical plasma mirror for the counter-propagating kilojoule-class petawatt LFEX laser system. Optics Express 30, 43491 (2022); https://doi.org/10.1364/oe.475945