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The burgeoning fields of spintronics and topological electronics require materials possessing a unique combination of properties: ferromagnetism, metallicity, and chemical stability. SrRuO3 (SRO) stands out as a compelling candidate due to its exceptional combination of these attributes. However, understanding its behavior under tensile strain, especially its thickness-dependent changes, remains elusive. This study employs machine-learning-assisted molecular beam epitaxy to investigate tensile-strained SRO films with thicknesses from 1 to 10 nm. This work complements the existing focus on compressive-strained SRO, opening a new avenue for exploring its hitherto concealed potential. Using soft x-ray magnetic circular dichroism, we uncover an intriguing interplay between film thickness, electronic structure, and magnetic properties. Our key findings reveal an intensified localization of Ru 4d t2g-O 2p hybridized states at lower thicknesses, attributed to the weakened orbital hybridization. Furthermore, we find a progressive reduction of magnetic moments for both Ru and O ions as film thickness decreases. Notably, a non-ferromagnetic insulating state emerges at a critical thickness of 1 nm, marking a pivotal transition from the metallic ferromagnetic phase. These insights emphasize the importance of considering thickness-dependent properties when tailoring SRO for next-generation spintronic and topological electronic devices. [ABSTRACT FROM AUTHOR]

The origin of magnetic anisotropy in magnetic compounds is a longstanding issue in materials science, and nonmagnetic ligand ions are considered to contribute little to magnetic anisotropy. Here, we introduce the concept of ligand-driven magnetic anisotropy in a complex transition-metal oxide. We conducted x-ray magnetic circular dichroism spectroscopies at the Ru and O edges in the 4d ferromagnetic metal SrRuO3. Systematic variation of the sample thickness in the range of ≤10 nm allowed us to control the localization of Ru 4d t2g states, which affects the magnetic coupling between the Ru and O ions. We observe that the orbital magnetic moment of the ligand O 2p orbitals induced through the charge transfer to the Ru 4d t2g states becomes anisotropic first, and the anisotropic magnetic moment of Ru and, therefore, the entire system is induced via magnetic coupling between Ru 4d and O 2p orbitals. [ABSTRACT FROM AUTHOR]

Purpose: The objective of this study was to evaluate the pulpal response to a newly-developed MMA resin cement (MultiBond, Tokuyama) when used for adhesively luting composite resin inlays. Materials and Methods: Cervical cavities were prepared in monkey teeth. The teeth were randomly divided into 3 groups. In the experimental group, a self-etching primer and a resin cement were applied to the cavities, and then hybrid composite inlays (Estenia, Kuraray) were inserted using freshly mixed resin cement. In the other groups, a zinc oxide/eugenol cement (Eugedain, Showa Yakuhin Kakou) or a glass-ionomer cement (Fuji II, GC) was used to fill the cavity. The teeth were then extracted after 3, 30, and 90 days, fixed in 10% buffered formalin solution, and prepared using routine histological techniques. Five-µm-thick sections were stained with hematoxylin and eosin, or Brown & Brenn gram stain for bacterial observation. Histopathological reactions in the pulp tissue and bacterial penetration along the cavity walls were assessed using a standardized score. Results: No serious inflammatory reactions in the pulp, such as necrosis or abscess formation, were observed in any of the experimental periods, except for 1 case after 30 days, in which a pulpal exposure was suspected. Disarrangement of the odontoblast layer and deposition of reparative dentin were the major reactions observed in this specimen. No bacterial penetration along the cavity walls was detected. The monkey pulpal response and in vivo sealing ability of the MMA resin cement in combination with the self-etching primer was considered as good as that of the glass-ionomer cement. Conclusion: The new MMA resin cement showed acceptable biological compatibility to the monkey pulp when used to adhesively lute composite resin inlays. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to evaluate the pulpal response of a fluoride-releasing one-step adhesive in nonexposed monkey teeth. Materials and Methods: Cervical Class V cavities were prepared in monkey teeth. The cavities were divided into three groups of different restorative materials. A one-step adhesive (SI-IB551, Shofu) was applied to the teeth, and the cavities were filled with a resin composite (Beautifil, Shofu). In the other two groups, a two-step adhesive (Imperva FluoroBond, Shofu) together with either a resin composite (Beautifil) or a glass-ionomer cement (Fuji II, GC) was placed in the cavities. The teeth were then extracted after 3, 30, and 90 days, fixed in 10% buffered formalin solution, and prepared according to routine histological techniques. Five-micrometer sections were stained with hematoxylin and eosin, or Brown & Brenn gram stain for bacterial observation. Four histological features, odontoblastic change, inflammatory cell infiltrate, reparative dentin formation, and the bacterial staining, were evaluated and compared. The results were compared statistically with significance defined as p < 0.05 (Kruskall- Wallis test). Results: Disarrangement of the odontoblasts and slight inflammatory cell infiltrations were the main initial reactions, while deposition of reparative dentin was the major long-term reaction in all groups. No statistically significant differences in the four histological features were seen among the restorative materials placed in the cavities (p > 0.05). No serious pulpal inflammatory reactions, such as necrosis or abscess formation, were observed in any of the experimental groups. Conclusion: The one-step adhesive showed acceptable biological compatibility with the monkey pulp, whereas the pulpal response to the system was minimally different from that of the glass-ionomer cement or the two-step self-etching adhesive. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the pulpal responses to a newly developed MMA-based self-etch resin cement, when used as a luting agent for indirect resin composite restoration, and to compare the results with those obtained from a total-etch luting agent, glass-ionomer cement, and amalgam restoration. Methods: 120 cervical cavities were prepared in monkey teeth and divided into four equal groups according to the restorative materials used: (1) the cavities were restored with resin composite inlays using a self-etch resin cement as a luting agent (M-Bond); (2) the cavities were also restored with resin composite inlays but using a total-etch resin cement as a luting agent (Super-Bond C&B); (3) the cavities were directly restored with glass-ionomer cement (Fuji II); or (4) the cavities were directly restored with amalgam (Dispersalloy). The restored teeth were extracted at 3, 30, or 90 days after restoration, then fixed in 10% neutral buffered formalin. The specimens were prepared using routine histopathological procedures. Five µm-thick sections were stained with hematoxylin and eosin or Brown & Brenn gram stain for bacterial observations. Histological responses in the pulpal tissue and bacterial penetration were observed under a light microscope and evaluated using standard scores. The results were statistically analyzed using the Kruskal-Wallis test (P< 005) Results: At all time intervals, no significant differences of pulpal inflammatory responses between M-Bond and Super-Bond C&B were observed (P> 0.05). Both resin cements showed no serious pulpal responses, such as necrosis or abscess formation. In general, both MMA based resin cements showed similar pulpal responses to those of glass-ionomer cement except for congestion of pulpal blood vessels at 3 days after restoration in winch glass-ionomer cement exhibited a lower level than that of the MMA based resin cements. For the group restored with amalgam, at 3 days after restoration, severe odontoblastic disorders and blood vessel congestions with a large infiltration of inflammatory cells were detected. At 30 and 90 days after restoration, slightly inflammatory irritations were observed irrespective of the materials used. Reparative dentin formation and bacterial penetration were found mostly in the group restored with amalgam. [ABSTRACT FROM AUTHOR]

We studied the genomic structure and biochemical properties of Schizosaccharomyces pombe mitochondrial single-stranded DNA binding protein (mtSSB). We first determined the full-length cDNA sequence of mtSSB and clarified the exon/intron structure of the mtSSB gene (rim1), including the transcription initiation and polyadenylation sites. The cDNA of rim1 gene encoded 150 amino acids and the sequence showed homology to eukaryotic mtSSB and Escherichia coli SSB. We overexpressed mtSSB as a His-tag fusion protein in E. coli and obtained an anti-mtSSB antibody. Gel filtration analysis of S. pombe cell extracts clarified that mtSSB has a tetrameric structure. We also immunochemically detected mtSSB in S. pombe cell extract and showed that 15,000 molecules of mtSSB tetramer are present in a single S. pombe cell. Mature mtSSB lacking the presequence was overexpressed in E. coli in tetrameric soluble form. The recombinant mtSSB bound a single-stranded oligonucleotide and ϕX174 virion DNA with almost identical binding activity as E. coli SSB. [ABSTRACT FROM AUTHOR]

This study evaluated the pulpal response and in-vivo microleakage of a flowable composite bonded with a self-etching adhesive and compared the results with a glass ionomer cement and amalgam. Cervical cavities were prepared in monkey teeth. The teeth were randomly divided into three groups. A self-etching primer system (Imperva FluoroBond, Shofu) was applied to the teeth in one of the experimental groups, and the cavities were filled with a flowable composite (SI-BF-2001-LF, Shofu). In the other groups, a glass ionomer cement (Fuji II, GC) or amalgam (Dispersalloy, Johnson & Johnson) filled the cavity. The teeth were then extracted after 3, 30 and 90 days, fixed in 10% buffered formalin solution and prepared according to routine histological techniques. Five micrometer sections were stained with hematoxylin and eosin or Brown and Brenn gram stain for bacterial observation. No serious inflammatory reaction of the pulp, such as necrosis or abscess formation, was observed in any of the experimental groups. Slight inflammatory cell infiltration was the main initial reaction, while deposition of reparative dentin was the major long-term reaction in all groups. No bacterial penetration along the cavity walls was detected in the flowable composite or glass ionomer cement except for one case at 30 days in the glass ionomer cement. The flowable composite bonded with self-etching adhesive showed an acceptable biological com- patibility to monkey pulp. The in vivo sealing ability of the flowable composite in combination with the self-etching adhesive was considered comparable to glass ionomer cement. Amalgam restorations without adhesive liners showed slight bacterial penetration along the cavity wall.