Low tibial valgization osteotomy for varus ankle arthritis - does age effect the outcome?

BACKGROUND: Evidence-based literature identifying the age limit for low tibial valgization osteotomy (LTO) is lacking to date. We addressed the following research questions: (1) is LTO effective for ankle arthritis in patients over 65 years?; (2) does patients' age alter the effectiveness of LTO?; and (3) does preoperative Takakura stage affect the degree of correction in patients over 65 years? METHODS: We retrospectively reviewed the radiographic and clinical findings of 49 cases which underwent LTO. Patients were divided into two groups according to age at operation (19 cases in group 1 aged ≥65 years and 30 cases in group 2 aged <65). Patients in a single group were regrouped into two subgroups according to preoperative Takakura stage (stage II + IIIA versus IIIB) to determine if the degree of correction varied in Takakura stage IIIB. RESULTS: Significant changes in radiographic parameters were observed with no significant differences in the amounts of correction between groups 1 and 2. Comparison of Takakura stage II + IIIA in group 1 to that in group 2 and stage IIIB in group 1 to that in group 2 revealed no significant differences in the amounts of correction. CONCLUSION: LTO could be indicated for patients over 65 years if patient selection was appropriate. LTO in patients over 65 years showed similar radiographic improvements to those in younger patients, and the correction was successfully maintained during the follow-up period. The correctional power of all radiographic parameters did not vary by preoperative Takakura stage. LEVEL OF EVIDENCE: Level III, comparative series.

Synthesis of Nitrogen-Doped Mesoporous Structures from Metal-Organic Frameworks and Their Utilization Enabling High Performances in Hybrid Sodium-Ion Energy Storages.

Sodium-ion energy storage is of the most attractive candidate for commercialization adoption due to the safety and cost demands of large-scale energy storage systems, but its low energy density, slow charging capability, and poor cycle stability are yet to be overcome. Here, a strategy is reported to realize high-performance sodium-ion energy storage using battery-type anode and capacitor-type cathode materials. First, nitrogen-doped mesoporous titanium dioxide (NMTiO2) structures are synthesized via the controlled pyrolysis of metal-organic frameworks. They exhibit interconnected open mesopores allowing fast ion transport and robust cycle stability with nearly 100% coulombic efficiency, along with rich redox-reactive sites allowing high capacity even at a high rate of ≈90 C. Moreover, assembling the NMTiO2 anode with the nitrogen-doped graphene (NG) cathode in an asymmetric full cell shows a high energy density exceeding its counterpart symmetric cell by more than threefold as well as robust cycle stability over 10 000 cycles. Additionally, it gives a high-power density close to 26 000 W kg-1 outperforming that of a conventional sodium-ion battery by several hundred fold, so that full cells can be charged within a few tens of seconds by the flexible photovoltaic charging and universal serial bus charging modules.

Tailoring open metal sites for selective capture of CO2 in isostructural metalloporphyrin porous organic networks.

Porphyrin-based isostructural porous organic networks have been synthesized by varying the central metal atoms to cobalt, nickel and copper. Their selectivities for CO2 capture over N2 and Ar are found to be enhanced as the heats of adsorption for CO2 are increased in the order of Co, Ni and Cu, while the pore structures are well maintained.

A facile synthesis of multi metal-doped rectangular ZnO nanocrystals using a nanocrystalline metal-organic framework template.

A multi metal (M: Fe, Co, and Ni)-doped rectangular ZnO nanocrystal (r-ZnO:M) was synthesised using nanocrystalline metal-organic framework-5 (n-MOF-5). After calcination in air, M-inserted n-MOF-5 led to r-ZnO:M of the wurtzite crystal structure with a small amount (<1%) of spinel ZnM2O4 phase. The inserted metal atoms of r-ZnO:M, replacing the Zn atoms of the wurtzite ZnO structure, were well-dispersed throughout the nanocrystal. Density functional theory calculations not only confirm the structural stability of wurtzite r-ZnO:M and negligible contribution of spinel ZnM2O4 but also elucidate the experimentally observed increase of visible light absorbance and appearance of ferromagnetism upon metal atom doping.