Honeycomb Layered Frameworks with Metallophilic Bilayers

Honeycomb layered frameworks with metallophilic bilayers have garnered traction in various disciplines due to their unique configuration and numerous physicochemical and topological properties, such as fast ionic conduction, coordination chemistry, and structural defects. These properties make them attractive for energy storage applications, leading to increased attention towards their metallophilic bilayer arrangements. This Review focuses on recent advancements in this field, including characterisation techniques like X-ray absorption spectroscopy and high-resolution transmission electron microscopy, particularly for silver-based oxides. It also highlights strategies related to cationic-deficient phases induced by topology or temperature, expanding the compositional space of honeycomb layered frameworks with a focus on cationic bilayer architectures. The Review further discusses theoretical approaches for understanding the bilayered structure, especially concerning critical phenomena at the monolayer-bilayer phase transition. Honeycomb layered frameworks are described as optimised lattices within the congruent sphere packing problem, equivalent to a specific two-dimensional conformal field theory. The monolayer-bilayer phase transition involves a 2D-to-3D crossover. Overall, this Review aims to provide a panoramic view of honeycomb layered frameworks with metallophilic bilayers and their potential applications in the emerging field of quantum matter. It is valuable for recent graduates and experts alike across diverse fields, extending beyond materials science and chemistry.Comment: 68 pages, 24 figure

Construction and Characterization of a PGN_0297 Mutant of Porphyromonas gingivalis: Evidence of the Contribution of PGN_0297 to Gingipain Activity

The periodontal pathogen Porphyromonas gingivalis shows colonial pigmentation on blood agar and produces gingipains (Kgp, RgpA, and RgpB), cysteine proteases involved in an organism’s virulence and pigmentation. We showed previously that deletion of the PGN_0300 gene abolished the pigmentation activity and reduced the proteolytic activity of gingipains. The role of the PGN_0297 gene, which consists of an operon with the PGN_0300 gene, is unclear. Herein we examined the effect of PGN_0297 gene deletion on the pigmentation and proteolytic activities and transcriptional levels of gingipains. A PGN_0297 gene deletion mutant (ΔPGN_0297) did not exhibit the pigmentation. The proteolytic activity of the gingipains was decreased in the culture supernatant and on the cell surface of ΔPGN_0297. The mutant ΔPGN_0297 failed to attenuate Akt phosphorylation at Thr308 and Ser473, but both phosphorylations were attenuated in the wild-type and its complementation strain. The deletion of PGN_0297 gene did not substantially affect the transcriptional levels of the gingipain genes kgp, rgpA, and rgpB. Taken together, these results indicate that PGN_0297 is closely involved in the secretion and maturation of gingipains

Honeycomb-Layered Oxides With Silver Atom Bilayers and Emergence of Non-Abelian SU(2) Interactions

Honeycomb-layered oxides with monovalent or divalent, monolayered cationic lattices generally exhibit myriad crystalline features encompassing rich electrochemistry, geometries, and disorders, which particularly places them as attractive material candidates for next-generation energy storage applications. Herein, global honeycomb-layered oxide compositions, Ag2M2TeO6 ((Formula presented.).) exhibiting (Formula presented.) atom bilayers with sub-valent states within Ag-rich crystalline domains of Ag6M2TeO6 and (Formula presented.) -deficient domains of (Formula presented.) ((Formula presented.)). The (Formula presented.) -rich material characterized by aberration-corrected transmission electron microscopy reveals local atomic structural disorders characterized by aperiodic stacking and incoherency in the bilayer arrangement of (Formula presented.) atoms. Meanwhile, the global material not only displays high ionic conductivity but also manifests oxygen-hole electrochemistry during silver-ion extraction. Within the (Formula presented.) -rich domains, the bilayered structure, argentophilic interactions therein and the expected (Formula presented.) sub-valent states ((Formula presented.), etc.) are theoretically understood via spontaneous symmetry breaking of SU(2) 7 U(1) gauge symmetry interactions amongst 3 degenerate mass-less chiral fermion states, justified by electron occupancy of silver (Formula presented.) and 5s orbitals on a bifurcated honeycomb lattice. This implies that bilayered frameworks have research applications that go beyond the confines of energy storage

Nonunion of a Stress Fracture at the Base of the Second Metatarsal in a Soccer Player Treated by Osteosynthesis with the Bridging Plate Fixation Technique

Background. A stress fracture of the second metatarsal base in soccer players is extremely rare. In this case study, we report a nonunion of a stress fracture at the base of the second metatarsal in a female soccer player who had persistent pain despite continued conservative treatment, who then was treated with the bridging plate fixation technique. Case Report. A 19-year-old female college soccer player complained of pain on the dorsum of her right midfoot during a game without history of trauma and was conservatively treated for 6 months. Radiographic examination showed an oblique fracture with small bone fragment at the proximal base of the second metatarsal and computed tomography demonstrated sclerotic change around the fracture site. We diagnosed her with nonunion of a stress fracture at the base of the second metatarsal and performed operative treatments using autogenous cancellous iliac bone grafting and plate fixation bridging a second metatarsal and medial cuneiform with a locking plate. At 4 months after the initial surgery, she was able to return to playing soccer at preinjury level without complications or pain. Conclusion. We report a rare case of nonunion of a stress fracture at the base of the second metatarsal in a female soccer player without underlying diseases. Surgical treatment was applied, because the conservative treatment was ineffective for 6 months and led to nonunion. The plate fixation technique bridging the second metatarsal and medial cuneiform was a useful option to attain the bone fusion for small fracture fragment for a treatment of nonunion of a stress fracture at the base of the second metatarsal

Persistent Hemarthrosis of the Knee after Arthroscopic Meniscal Repair

Introduction. In this case report, we report a patient with complicated with persistent hemarthrosis following arthroscopic meniscal repair. Case Presentation. A 41-year-old male patient presented with persistent swelling of the knee 6 months after arthroscopic meniscal repair and partial meniscectomy performed for lateral discoid meniscal tear. The initial surgery was performed at another hospital. Four months after the surgery, swelling of the knee was noted when he resumed running. At his initial visit to our hospital, intra-articular blood accumulation was revealed via joint aspiration. A second arthroscopic examination performed 7 months after the initial procedure showed healing of the meniscal repair site and synovial proliferation. The suture materials identified during the arthroscopy were removed. Histological examination of the resected synovial tissue showed inflammatory cell infiltration and neovascularization. In addition, a multinucleated giant cell was identified in the superficial layer. After the second arthroscopic surgery, the hemarthrosis did not recur, and the patient was able to resume running without symptom one and a half years post-surgery. Conclusion. Bleeding from the proliferated synovia at or near the periphery of the lateral meniscus was thought to be the cause of the hemarthrosis as a rare complication following arthroscopic meniscal repair