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The effect of ionospheric delay on the ground-based augmentation system under normal conditions can be mitigated by determining the value of the nominal ionospheric gradient (σvig). The nominal ionospheric gradient is generally obtained from Continuously Operating Reference Stations data by using the spatial single-difference method (mixed-pair, station-pair, or satellite-pair) or the temporal single-difference method (time-step). The time-step method uses only a single receiver, but it still contains ionospheric temporal variations. We introduce a corrected time-step method using a fixed-ionospheric pierce point from the geostationary equatorial orbit satellite and test it through simulations based on the global ionospheric model. We also investigate the effect of satellite paths on the corrected time-step method in the region of the equator, which tends to be in a more north–south direction and to have less coverage for the east–west ionospheric gradient. This study also addresses the limitations of temporal variation correction coverage and recommends using only the correction from self-observations. All processes are developed under simulations because observational data are still difficult to obtain. Our findings demonstrate that the corrected time-step method yields σvig values consistent with other approaches.

Background: Breast reconstruction is crucial for patients who have undergone mastectomy for breast cancer. Our bioabsorbable implants comprising an outer poly-l-lactic acid mesh and an inner component filled with collagen sponge promote and retain adipogenesis in vivo without the addition of exogenous cells or growth factors. In this study, we evaluated adipogenesis over time histologically and at the gene expression level using this implant in a rodent model. Methods: The implants were inserted in the inguinal and dorsal regions of the animals. At 1, 3, 6, and 12 months post-operation, the weight, volume, and histological assessment of all newly formed tissue were performed. We analyzed the formation of new adipose tissue using multiphoton microscopy and RNA sequencing. Results: Both in the inguinal and dorsal regions, adipose tissue began to form 1 month post-operation in the peripheral area. Angiogenesis into implants was observed until 3 months. At 6 months, microvessels matured and the amount of newly generated adipose tissue peaked and was uniformly distributed inside implants. The amount of newly generated adipose tissue decreased from 6 to 12 months but at 12 months, adipose tissue was equivalent to the native tissue histologically and in terms of gene expression. Conclusions: Our bioabsorbable implants could induce normal adipogenesis into the implants after subcutaneous implantation. Our implants can serve as a novel and safe material for breast reconstruction without requiring exogenous cells or growth factors.

Background: Symptomatic distal interphalangeal joint osteoarthritis is a common joint disease that causes hand disability and reduces quality of life. There are few conservative treatment options for this condition. The purpose of this study was to investigate the effect of traction treatment on symptomatic distal interphalangeal joint osteoarthritis. Methods: This prospective, longitudinal study involved multiple time-series observations and within-subject controls. The most painful distal interphalangeal joints in patients with hand osteoarthritis were treated by daily, 15-min joint traction at home using a finger trap orthosis. The corresponding contralateral digits were used as within-subject controls. The primary outcome measure was two-point pinch strength, and the secondary outcome measures were radiographic findings and treatment adherence. Longitudinal and pairwise comparison analyses of the treated and control digits examined improvements in two-point pinch strength at months 1, 3, and 6 from baseline. The durability of treatment effects after treatment discontinuation was investigated at month 12. Results: Eighteen treated digits and 18 corresponding control digits were eligible for analysis. There was a significant increase in two-point pinch strength after 1-month traction, and this increase was maintained until month 6 despite the absence of radiographic changes. Compared to controls, significant improvement in two-point pinch strength relative to baseline was seen at every observation time point, with a moderate to large effect size. There was no time–treatment interaction. Treatment adherence was high. At months 3 and 6, around 60–80 % of digits were voluntarily treated. Pinch strength was comparable between months 6 and 12, with greater improvement than in the control group. Conclusion: Joint traction treatment can improve pinch strength in symptomatic distal interphalangeal joint osteoarthritis. Larger, randomized studies on traction treatment and the effect on hand function are warranted.

Perfluorosulfonic acid (PFSA) polymers are used as electrolyte membranes in polymer electrolyte fuel cells. To investigate the effect on proton conductivity through structural orientation control, we added 1,2,4-triazole to PFSA films during casting to impart anisotropy to the ion-cluster structure of the films. The proton conductivities of the films were found to be high in the film-surface direction and low in the film-thickness direction. Structural analysis using small-angle X-ray scattering suggested that the anisotropy in proton conductivity was due to anisotropy in the ion-cluster structure, which in turn was attributed to the formation of a phase-separated structure via strong bonding between sulfonic acid groups and 1,2,4-triazole during cast film formation and the surface segregation of fluorine. We expect the findings of this study to aid in the fabrication of PFSA films with controlled ion clusters.

Serial sectioning and 3D image reconstruction methods were applied to elucidate the structures of the apices of root vascular cylinders (VCs) in taxa of the Poaceae: Zea mays “Honey Bantam”, Z. mays ssp. mexicana, Hordeum vulgare and Oryza sativa. The primary and nodal roots were investigated. Observations were performed using high-quality sectioning and 3D image-processing techniques improved and developed by the authors. We found that a quiescent uniseriate plerome was located at the most distal part of each VC. Vascular initials were located immediately basipetally to the plerome as a specific uniseriate layer that could be classified into central and peripheral initials that produced all the cells in the VC. No supplying of cells from the plerome to the vascular initials was observed. Numerical analysis revealed a “boundary point” along the root axis where the rate of increase of the vascular cell number markedly declined, and the VC diameter, number of vascular cells, and number of late-maturing metaxylem vessels (LMXs) at that point showed a similar relationship among the taxa and the types of roots examined (primary vs. nodal). The plerome and vascular initials layer can be considered independent after seed germination in these taxa. A boundary point at which procambial cell proliferation sharply declined was identified. The diameters of the VCs, number of LMXs, and number of vascular cells at the boundary point were found to be strongly related to each other.