Mechanochemically Enabled Metastable Niobium Tungsten Oxides.

Metastable compounds have greatly expanded the synthesizable compositions of solid-state materials and have attracted enormous amounts of attention in recent years. Especially, mechanochemically enabled metastable materials synthesis has been very successful in realizing cation-disordered materials with highly simple crystal structures, such as rock salts. Application of the same strategy for other structural types, especially for non-close-packed structures, is peculiarly underexplored. Niobium tungsten oxides (NbWOs), a class of materials that have been under the spotlight because of their diverse structural varieties and promising electrochemical and thermoelectric properties, are ideally suited to fill such a knowledge gap. In this work, we develop a new series of metastable NbWOs and realize one with a fully cation-disordered structure. Furthermore, we find that metastable NbWOs transform to a cation-disordered cubic structure when applied as a Li-ion battery anode, highlighting an intriguing non-close-packed-close-packed conversion process, as evidenced in various physicochemical characterizations, in terms of diffraction, electronic, and vibrational structures. Finally, by comparing the cation-disordered NbWO with other trending cation-disordered oxides, we raise a few key structural features for cation disorder and suggest a few possible research opportunities for this field.

Na2.5 Cr0.5 Zr0.5 Cl6 : A New Halide-Based Fast Sodium-Ion Conductor.

All-solid-state batteries employing solid electrolytes (SEs) have received widespread attention due to their high safety. Recently, lithium halides are intensively investigated as promising SEs while their sodium counterparts are less studied. Herein, a new sodium-ion conductor with a chemical formula of Na2.5 Cr0.5 Zr0.5 Cl6 is reported, which exhibits high room temperature ionic conductivity of 0.1 mS cm-1 with low migration energy barrier of ≈0.41 eV. Na2.5 Cr0.5 Zr0.5 Cl6 has a Fm-3m structure with 41.67 mol.% of cationic vacancies owing to the occupation of Cr (8.33 mol.%) and Zr (8.33 mol.%) ions at Na sites. Supercell calculations show that the lowest columbic energy configuration has Cr/Zr/V (where V is the vacancy) clusters in the structure. Nonetheless, the clusters have mixed effects on the sodium ion conduction pathway, based on the Bond Valence Energy Landscape calculation. A global 3D Na-ion transport percolation network can be revealed in the lowest energy supercell. Effective pathways are connected through the NaCl6 and VCl6 nodes. Besides, Raman spectroscopy and 23 Na solid-state nuclear magnetic resonance spectroscopy further prove the tunable structure of the SEs with different Cr to Zr ratios. The optimization between the concentration of Na+ and vacancies is crucial to create an improved network of Na+ diffusion channels.

Sustainable Anionic Redox by Inhibiting Li Cross-Layer Migration in Na-Based Layered Oxide Cathodes.

The irrational utilization of an anionic electron often accompanies structural degradation with an irreversible cation migration process upon cycling in sodium-layered oxide cathodes. Moreover, the insufficient understanding of the anionic redox involved cation migration makes the design strategies of high energy density electrodes even less effective. Herein, a P3-Na0.67Li0.2Fe0.2Mn0.6O2 (P3-NLFM) cathode is proposed with the in-plane disordered Li distribution after an in-depth remolding of the Li ribbon-ordered P3-Na0.6Li0.2Mn0.8O2 (P3-NLM) layered oxide. The disordered Li sublattice in the transition metal slab of P3-NLFM leads to the dispersed |O2p orbitals, the lowered charge transfer gap, and the suppressed phase transition at high voltages. Then the enhanced Mn-O interaction and electronic stability are disclosed by the crystal orbital Hamilton population (COHP) analysis at high voltage in P3-NLFM. Furthermore, ab initio molecular dynamics (AIMD) simulation suggests the order/disorder of the transition metal layer is highly correlated with the stability of the Li sublattice. The cross-layer migration and loss of Li in P3-NLM are suppressed in P3-NLFM to enable the high reversibility upon cycling. As a result, the P3-NLFM delivers a high capacity of 163 mAh g-1 without oxygen release and an enhanced capacity retention of 81.9% (vs 42.9% in P3-NLM) after 200 cycles, which constitutes a promising approach for sustainable oxygen redox in rechargeable batteries.

Promoting high-voltage stability through local lattice distortion of halide solid electrolytes.

Stable solid electrolytes are essential to high-safety and high-energy-density lithium batteries, especially for applications with high-voltage cathodes. In such conditions, solid electrolytes may experience severe oxidation, decomposition, and deactivation during charging at high voltages, leading to inadequate cycling performance and even cell failure. Here, we address the high-voltage limitation of halide solid electrolytes by introducing local lattice distortion to confine the distribution of Cl-, which effectively curbs kinetics of their oxidation. The confinement is realized by substituting In with multiple elements in Li3InCl6 to give a high-entropy Li2.75Y0.16Er0.16Yb0.16In0.25Zr0.25Cl6. Meanwhile, the lattice distortion promotes longer Li-Cl bonds, facilitating favorable activation of Li+. Our results show that this high-entropy halide electrolyte boosts the cycle stability of all-solid-state battery by 250% improvement over 500 cycles. In particular, the cell provides a higher discharge capacity of 185 mAh g-1 by increasing the charge cut-off voltage to 4.6 V at a small current rate of 0.2 C, which is more challenging to electrolytes|cathode stability. These findings deepen our understanding of high-entropy materials, advancing their use in energy-related applications.

Novel Low-Strain Layered/Rocksalt Intergrown Cathode for High-Energy Li-Ion Batteries.

Both layered- and rocksalt-type Li-rich cathode materials are drawing great attention due to their enormous capacity, while the individual phases have their own drawbacks, such as great volume change for the layered phase and low electronic and ionic conductivities for the rocksalt phase. Previously, we have reported the layered/rocksalt intergrown cathodes with nearly zero-strain operation, while the use of precious elements hinders their industrial applications. Herein, low-cost 3d Mn4+ ions are utilized to partially replace the expensive Ru5+ ions, to develop novel ternary Li-rich cathode material Li1+x[RuMnNi]1-xO2. The as-designed Li1.15Ru0.25Mn0.2Ni0.4O2 is revealed to have a layered/rock salt intergrown structure by neutron diffraction and transmission electron microscopy. The as-designed cathode exhibits ultrahigh lithium-ion reversibility, with 0.86 (231.1 mAh g-1) out of a total Li+ inventory of 1.15 (309.1 mAh g-1). The X-ray absorption spectroscopy and resonant inelastic X-ray scattering spectra further demonstrate that the high Li+ storage of the intergrown cathode is enabled by leveraging cationic and anionic redox activities in charge compensation. Surprisingly, in situ X-ray diffraction shows that the intergrown cathode undergoes extremely low-strain structural evolution during the charge-discharge process. Finally, the Mn content in the intergrown cathodes is found to be tunable, providing new insights into the design of advanced cathode materials for high-energy Li-ion batteries.

Over-Stoichiometric Metastabilization of Cation-Disordered Rock Salts.

Cation-disordered rock salts (DRXs) are well known for their potential to realize the goal of achieving scalable Ni- and Co-free high-energy-density Li-ion batteries. Unlike in most cathode materials, the disordered cation distribution may lead to more factors that control the electrochemistry of DRXs. An important variable that is not emphasized by research community is regarding whether a DRX exists in a more thermodynamically stable form or a more metastable form. Moreover, within the scope of metastable DRXs, over-stoichiometric DRXs, which allow relaxation of the site balance constraint of a rock salt structure, are particularly underexplored. In this work, these findings are reported in locating a generally applicable approach to "metastabilize" thermodynamically stable Mn-based DRXs to metastable ones by introducing Li over-stoichiometry. The over-stoichiometric metastabilization greatly stimulates more redox activities, enables better reversibility of Li deintercalation/intercalation, and changes the energy storage mechanism. The metastabilized DRXs can be transformed back to the thermodynamically stable form, which also reverts the electrochemical properties, further contrasting the two categories of DRXs. This work enriches the structural and compositional space of DRX families and adds new pathways for rationally tuning the properties of DRX cathodes.

Enhancing Ionic Transport and Structural Stability of Lithium-Rich Layered Oxide Cathodes via Local Structure Regulation.

Lithium-rich manganese-based layered oxides (LRM) have garnered considerable attention as cathode materials due to their superior performance. However, the inherent structural degradation and obstruction of ion transport during cycling lead to capacity and voltage decay, impeding their practical applications. Herein, an Sb-doped LRM material with local spinel phase is reported, which has good compatibility with the layered structure and provides 3D Li+ diffusion channels to accelerate Li+ transport. Additionally, the strong Sb-O bond enhances the stability of the layered structure. Differential electrochemical mass spectrometry indicates that highly electronegative Sb doping effectively suppresses the release of oxygen in the crystal structure and mitigates successive electrolyte decomposition, thereby reducing structural degradation of the material. As a result of this dual-functional design, the 0.5 Sb-doped material with local spinel phases exhibits favorable cycling stability, retaining 81.7% capacity after 300 cycles at 1C, and an average discharge voltage of 1.87 mV per cycle, which is far superior to untreated material with retention values of 28.8% and 3.43 mV, respectively. This study systematically introduces Sb doping and regulates local spinel phases to facilitate ion transport and alleviate structural degradation of LRM, thereby suppressing capacity and voltage fading, and improving the electrochemical performance of batteries.

A New Zinc Salt Chemistry for Aqueous Zinc-Metal Batteries.

Aqueous zinc-ion batteries (ZIBs) are promising energy storage solutions with low cost and superior safety, but they suffer from chemical and electrochemical degradations closely related to the electrolyte. Here, a new zinc salt design and a drop-in solution for long cycle-life aqueous ZIBs are reported. The salt Zn(BBI)2 with a rationally designed anion group, N-(benzenesulfonyl)benzenesulfonamide (BBI- ), has a special amphiphilic molecular structure, which combines the benefits of hydrophilic and hydrophobic groups to properly tune the solubility and interfacial condition. This new zinc salt does not contain fluorine and is synthesized via a high-yield and low-cost method. It is shown that 1 m Zn(BBI)2 aqueous electrolyte with a widened cathodic stability window effectively stabilizes Zn metal/H2 O interface, mitigates chemical and electrochemical degradations, and enables both symmetric and full cells using a zinc-metal electrode.

Open exploration, ulnar osteotomy and annular ligament reduction for chronic Monteggia fracture in children / 中华创伤骨科杂志

Objective:To investigate the efficacy of open exploration, ulnar osteotomy and annular ligament reduction (three-in-one surgery) in the treatment of chronic Monteggia fracture in children.Methods:The data were analyzed retrospectively of the 35 children with chronic Monteggia fracture who had been admitted to Department of Pediatric Orthopaedics, Tianjin University from June 2017 to September 2021. There were 22 boys and 13 girls, and 19 left and 16 right sides, with an age of (6.8±2.5) years. Anterolateral dislocation of the radial head occurred in 30 cases and anterolateral dislocation in 5 ones. The time from injury to operation was (17.9±9.9) months. All patients were treated with three-in-one surgery. The elbow flexion and extension, forearm rotation and The Hospital for Special Surgery (HSS) elbow score were measured and compared in all patients at 12 months after operation. Their complications were also recorded.Results:All children were followed up for 12 months. The osteotomy ends of the ulna achieved bony union 1.5 to 4.0 months after operation. The elbow extension (-1.0°±5.9°) and flexion (128.5°±4.9°) at 12 months after operation were significantly improved compared with those before operation (-9.3°±18.0° and 108.4°±17.3°) ( P<0.05). The forearm pronation (61.5°±19.4°) at 12 months after operation was significantly limited compared with that before operation (72.7°±22.4°) ( P<0.05). There was no significant difference between the forearm supination (86.7°±4.5°) at 12 months after operation and that before operation (81.0°±17.4°) ( P>0.05). The HSS elbow score at 12 months after operation (93.5±5.2) was significantly higher than that (80.6±9.3) before operation ( P<0.05). The efficacy evaluated by the HSS elbow score at 12 months after operation was excellent in 21 cases, good in 12 cases, and fair in 2 cases, giving an excellent and good rate of 94.3% (33/35). Postoperative re-subluxation was observed in one patient. Conclusion:Open exploration, ulnar osteotomy and annular ligament reduction are a safe and effective three-in-one surgery for chronic Monteggia fracture in children, because it may lead to significantly improved elbow flexion and extension after operation, though the forearm pronation may be limited.

Treatment of open tibial fractures in children with composite pin-rod external fixation / 中华创伤骨科杂志

Objective:To explore the clinical efficacy of composite pin-rod external fixation in the treatment of open tibial fractures in children.Methods:The clinical data were retrospectively analyzed of the 21 pediatric patients with open tibial fracture who had been treated at Department of Pediatric Orthopeadics, Tianjin University by composite pin-rod external fixation from January 2019 to December 2021. There were 15 boys and 6 girls, and 9 left sides and 12 right sides. The age at the time of operation was (8.6±4.1) months. According to the Gustilo-Anderson classification, there were 3 cases of type Ⅰ, 12 cases of type Ⅱ, 3 cases of type ⅢA, 1 case of type ⅢB, and 2 cases of type ⅢC. Twenty cases had a concomitant fibular fracture, 3 cases multiple injuries, and 3 cases a segmental fracture. All the operations were performed at the emergency department. After debridement, the fractures were reduced and immobilized with a triangle external fixation of composite pin-rod system. In the patients whose conditions permitted, the wounds were closed at one stage, and no other external fixation was added after operation. Wound healing, fracture healing, frame time, knee and ankle functional results and complications were evaluated.Results:All patients were followed up for (20.7±15.8) months. Primary wound closure was achieved in 18 cases; the wound was covered by vacuum sealing drainage after debridement and reverse skin removal in the other 3 cases, of which 2 healed smoothly, and 1 was complicated with superficial infection of Gustilo type ⅢC treated eventually by an anterolateral thigh flap. Fractures healed satisfactorily in 20 cases, with a frame time of (4.5±1.7) months. At the last follow-up, there was no significant difference in the range of motion of the knee and ankle joints on the affected side compared with the uninjured side ( P>0.05). According to the Johner-Wruhs evaluation criteria, the functional recovery was excellent in 16 cases and good in 4 cases. Fracture nonunion happened in one child after skin flap operation, but fracture occurred again after reoperation for fracture, yielding a poor Johner-Wruhs evaluation. Needle tract infection was found in 9 cases but responded to therapy with no other complications. Conclusions:In the treatment of open tibial fractures in children, the composite pin-rod external fixation may lead to satisfactory clinical outcomes. It is easy in operation, provides stable fixation, and allows early rehabilitation after surgery. It can be used as a terminal treatment for wounds that can be closed at one stage.

Therapeutic Mechanism of Kai Xin San on Alzheimer's Disease Based on Network Pharmacology and Experimental Validation / 中国结合医学杂志

OBJECTIVE@#To explore the specific pharmacological molecular mechanisms of Kai Xin San (KXS) on treating Alzheimer's disease (AD) based on network pharmacology and experimental validation.@*METHODS@#The chemical compounds of KXS and their corresponding targets were screened using the Encyclopedia of Traditional Chinese Medicine (ETCM) database. AD-related target proteins were obtained from MalaCards database and DisGeNET databases. Key compounds and targets were identified from the compound-target-disease network and protein-protein interaction (PPI) network analysis. Functional enrichment analysis predicted the potential key signaling pathways involved in the treatment of AD with KXS. The binding affinities between key ingredients and targets were further verified using molecular docking. Finally, the predicted key signaling pathway was validated experimentally. Positioning navigation and space search experiments were conducted to evaluate the cognitive improvement effect of KXS on AD rats. Western blot was used to further examine and investigate the expression of the key target proteins related to the predicted pathway.@*RESULTS@#In total, 38 active compounds and 469 corresponding targets of KXS were screened, and 264 target proteins associated with AD were identified. The compound-target-disease and PPI networks identified key active ingredients and protein targets. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis suggested a potential effect of KXS in the treatment of AD via the amyloid beta (A β)-glycogen synthase kinase-3 beta (GSK3 β)-Tau pathway. Molecular docking revealed a high binding affinity between the key ingredients and targets. In vivo, KXS treatment significantly improved cognitive deficits in AD rats induced by Aβ1-42, decreased the levels of Aβ, p-GSK3β, p-Tau and cyclin-dependent kinase 5, and increased the expressions of protein phosphatase 1 alpha (PP1A) and PP2A (P<0.05 or P<0.01).@*CONCLUSION@#KXS exerted neuroprotective effects by regulating the Aβ -GSK3β-Tau signaling pathway, which provides novel insights into the therapeutic mechanism of KXS and a feasible pharmacological strategy for the treatment of AD.

Lithiated Prussian blue analogues as positive electrode active materials for stable non-aqueous lithium-ion batteries.

Prussian blue analogues (PBAs) are appealing active materials for post-lithium electrochemical energy storage. However, PBAs are not generally suitable for non-aqueous Li-ion storage due to their instability upon prolonged cycling. Herein, we assess the feasibility of PBAs with various lithium content for non-aqueous Li-ion storage. We determine the crystal structure of the lithiated PBAs via neutron powder diffraction measurements and investigate the influence of water on structural stability and Li-ion migration through operando X-ray diffraction measurements and bond valence simulations. Furthermore, we demonstrate that a positive electrode containing Li2-xFeFe(CN)6⋅nH2O (0 ≤ x ≤ 2) active material coupled with a Li metal electrode and a LiPF6-containing organic-based electrolyte in coin cell configuration delivers an initial discharge capacity of 142 mAh g-1 at 19 mA g-1 and a discharge capacity retention of 80.7% after 1000 cycles at 1.9 A g-1. By replacing the lithium metal with a graphite-based negative electrode, we also report a coin cell capable of cycling for more than 370 cycles at 190 mA g-1 with a stable discharge capacity of about 105 mAh g-1 and a discharge capacity retention of 98% at 25 °C.

Slight compositional variation-induced structural disorder-to-order transition enables fast Na+ storage in layered transition metal oxides.

The omnipresent Na+/vacancy orderings change substantially with the composition that inevitably actuate the ionic diffusion in rechargeable batteries. Therefore, it may hold the key to the electrode design with high rate capability. Herein, the influence of Na+/vacancy ordering on Na+ mobility is demonstrated firstly through a comparative investigation in P2-Na2/3Ni1/3Mn2/3O2 and P2-Na2/3Ni0.3Mn0.7O2. The large zigzag Na+/vacancy intralayer ordering is found to accelerate Na+ migration in P2-type Na2/3Ni1/3Mn2/3O2. By theoretical simulations, it is revealed that the Na+ ordering enables the P2-type Na2/3Ni1/3Mn2/3O2 with higher diffusivities and lower activation energies of 200 meV with respect to the P3 one. The quantifying diffusional analysis further prove that the higher probability of the concerted Na+ ionic diffusion occurs in P2-type Na2/3Ni1/3Mn2/3O2 due to the appropriate ratio of high energy ordered Na ions (Naf) occupation. As a result, the interplay between the Na+/vacancy ordering and Na+ kinetic is well understood in P2-type layered cathodes.

Study of low-dose CT scan volume rendering technology in evaluating the physeal bar in children / 中华骨科杂志

Objective:To evaluate the feasibility of CT volume rendering technology in the assessment of the physeal bar in children.Methods:A retrospective analysis of the relevant CT data of 20 patients with physeal bar from January 2019 to December 2021, 13 boys and 7 girls, age 9.94±2.91 years. The etiology included 17 cases of trauma, 1 cases of tumor, and 2 cases of unknown. The affected sites included 9 cases of distal femur, 5 cases of proximal tibia, 3 cases of distal tibia, and 3 cases of distal radius. Evaluate using volume rendering technology and traditional surface reconstruction technology respectively and the index include the size and type of physeal bar.Results:All the children were successfully examined at one time, and none of them required sedation. The average exposure time was 3.81±0.83 s. During scanning, only low-dose radiation was performed on the affected joints, and routine radiation protection was performed. Using volume rendering technology to evaluate the proportion of the physeal bar, the results obtained by the three testers were 25.36%±15.36%, 24.75%±16.18%, 26.70%±17.72%, and the intraclass correlation coefficient value ( ICC) was 0.976, the three repeated measurements by one tester were 25.36%±15.36%, 25.41%±15.20%, 25.74%±16.00% ( ICC=0.990). Compared with the traditional curved planar reconstruction technical evaluation, the results obtained by the three testers were 28.36%±16.74%, 23.66%±19.87%, 35.25%±15.92% ( ICC=0.737), the three repeated measurement results by one tester were 28.36%±16.74%, 31.66%±13.06%, 30.89%±12.52% ( ICC=0.875). The volume rendering technology was better than the curved planar reconstruction technique. Paired t test was performed on the measurement results of three evaluators and the three repeated measurements of the same evaluator, and the differences were statistically significant ( P<0.05). The same results were acquired by using volume rendering technology to evaluate the type of phseal bar with three testers; but there were 18 cases had the same results by using curved planar reconstruction technology and 2 cases had differences, showing the volume rendering technology was more accurate. Conclusion:Low-dose CT scanning volume rendering technology is an effective method to evaluate the physeal bar in children. It can more intuitively and accurately evaluate the proportion and type of the bar while reducing the radiation exposure of children. The consistency with inter-group and intra-group is better than traditional curved planar reconstruction technique with good reproducibility and clinical significance.

Application of interlocking intramedullary nailing in fibrous dysplasia of proximal femur / 中华骨科杂志

Objective:To retrospectively analyze and evaluate the effect of interlocking intramedullary nail in the treatment of proximalfemoral fibrous dysplasia (FD) and to discuss its application techniques and treatment strategies.Methods:The patients with proximal femoral FD who received treatment with interlocking intramedullary nail in our department from April 2014 to August 2018 were retrospectively reviewed. The inclusion criteria included having complete data with more than 3 years follow-up. A total of 31 cases with 32 thighs were included in the present study. Among them, there were 24 males and 7 females. The mean age at operation was 11.4±2.3 years. The mean follow-up duration was 3.9±1.1 years. The surgical methods were osteotomy or in situ interlocking intramedullary nailing, and femoral neck reconstruction nails pass through the epiphyseal plate in some cases. Preoperative, postoperative and final follow-up radiographic changes, including femoral neck shaft angle, proximal femoral diaphyseal deformity, and femoral alignment were compared. Univariate analysis of the influencing factors of postoperative femoral neck shaft angle loss.Results:In this group, 13 patients had coxa varus deformity, and the angle of the neck shaft was 107.3±7.1°, and 23 patients had the bending deformity of the proximal femur, and angled 29.5°±9.1°. 10 cases of coxa varus combined with proximal femoral diaphyseal deformity received double osteotomy and internal fixation, 17cases of simple coxa varus or diaphyseal deformity received single osteotomy and internal fixation, and 5 cases had no significant deformity, underwent in situ intramedullary nailing due to pathological fractures and pain. Postoperative femoral neck shaft angle was 133.2°±5.2°. Complete correction of proximal femoral flexion deformity was obtained and the diaphyseal axis was within the normal range. At the last follow-up, the neck shaft angle of 7 patients (21.9%, 7/32) decreased from 133.6°±3.9° to 125.7°±3.4°. Univariate analysis showed that the proportion of neck shaft angle loss in cases with proximal femoral locking nails passing through the epiphyseal plate was significantly lower than that in the cases without (0 vs. 43.8%, χ 2=6.58, P=0.010). Conclusion:The application of interlocking intramedullary nails in the treatment of proximal femoral fibrous dysplasia can achieve good results, according to the situation of coxa varus or diaphysis bending deformity, single or double osteotomy can be performed. There is a risk of femoral neck shaft angle loss after surgery, which can be avoided by femoral neck reconstruction locking screw fixation crossing epiphyseal plate.

Solid-state rigid-rod polymer composite electrolytes with nanocrystalline lithium ion pathways.

A critical challenge for next-generation lithium-based batteries lies in development of electrolytes that enable thermal safety along with the use of high-energy-density electrodes. We describe molecular ionic composite electrolytes based on an aligned liquid crystalline polymer combined with ionic liquids and concentrated Li salt. This high strength (200 MPa) and non-flammable solid electrolyte possesses outstanding Li+ conductivity (1 mS cm-1 at 25 °C) and electrochemical stability (5.6 V versus Li|Li+) while suppressing dendrite growth and exhibiting low interfacial resistance (32 Ω cm2) and overpotentials (≤120 mV at 1 mA cm-2) during Li symmetric cell cycling. A heterogeneous salt doping process modifies a locally ordered polymer-ion assembly to incorporate an inter-grain network filled with defective LiFSI and LiBF4 nanocrystals, strongly enhancing Li+ conduction. This modular material fabrication platform shows promise for safe and high-energy-density energy storage and conversion applications, incorporating the fast transport of ceramic-like conductors with the superior flexibility of polymer electrolytes.

Layered-rocksalt intergrown cathode for high-capacity zero-strain battery operation.

The dependence on lithium-ion batteries leads to a pressing demand for advanced cathode materials. We demonstrate a new concept of layered-rocksalt intergrown structure that harnesses the combined figures of merit from each phase, including high capacity of layered and rocksalt phases, good kinetics of layered oxide and structural advantage of rocksalt. Based on this concept, lithium nickel ruthenium oxide of a main layered structure (R[Formula: see text]m) with intergrown rocksalt (Fm[Formula: see text]m) is developed, which delivers a high capacity with good rate performance. The interwoven rocksalt structure successfully prevents the anisotropic structural change that is typical for layered oxide, enabling a nearly zero-strain operation upon high-capacity cycling. Furthermore, a design principle is successfully extrapolated and experimentally verified in a series of compositions. Here, we show the success of such layered-rocksalt intergrown structure exemplifies a new battery electrode design concept and opens up a vast space of compositions to develop high-performance intergrown cathode materials.

How does containment surgery alter the natural evolution in early stage of Perthes disease / 中华骨科杂志

Objective:Course of evolution observed relatively early Perthes disease in children surgically treated and conservative, explore the significance of early surgical treatment of Perthes disease.Methods:From January 1997 to December 2017, 632 children with Perthes disease were admitted. According to the inclusion and exclusion criteria, a total of 67 children were included in this study. Surgical group: 35 cases, 32 males and 3 females, age ranged from 7.0 to 11.8 years, with an average 8.3±1.0 years old, 21 cases on the left side and 14 cases on the right side. Conservative group: 32 cases, 24 males and 8 females, age ranged from 7.1 to 12.0 years old, with an average of 8.4±1.4 years old, 22 cases on the left side and 10 cases on the right side. The pelvic orthosis and frog position were taken every 3 months, and the evolution of Perthes disease was evaluated by referring to the modified Waldenstr?m staging. In the series of observations, no modified Waldenstr?m IIb stage was found to skip the fragmentation stage. After the healing period, the pelvic orthosis and frog position were evaluated according to the Stulburg classification results, and the ratio of the width of the metaphyseal end of the affected side to the contralateral side and the height of the femoral head epiphysis were measured.Results:The time required to enter stage IIIa, surgical group: range from 0.1 to 1.5 years, with an average of 0.58±0.33 years, conservative group: range from 0.4 to 1.8 years, with an average of 0.96±0.30 years, it takes both to enter the repair phase The time difference was statistically significant ( t=5.259, P<0.05); children whose disease course skipped the fragmentation stage, surgical group: 11 cases (31%), conservative group: 5 cases (16%), the difference is statistically significant ( χ2=22.626, P<0.05). The ratio of the affected side to the uninfected side of the metaphysis: surgical group: range 101%-123%, with an average of 108.0%±6.0%. Conservative group: range 101%-148%, with an average of 115.8%±11.2%. The difference in the ratio between the affected side and the healthy side of the metaphysis was statistically significant ( t=3.450, P<0.05). The ratio of the affected side to the healthy side of the height of the femoral head epiphysis: surgical group: range 61%-96%, with an average of 82.5%±8.2%. Conservative group: range 33%-92%, with an average of 74.7%±1.3%. There was a statistically significant difference in the ratio of the height of the femoral head epiphysis between the affected side and the healthy side ( t=2.921, P<0.05). Stulberg classification, surgical group: Type I hip joints 29 hips, Type II hip joints 6 hips, Type III hips 0 hips; conservative group: Type I hips 16 hips, Type II hips 10 hips, Type III hips 6 hips. There was a statistically significant difference in the Stulberg classification after the two entered stage IV ( Z=3.386, P<0.05). Conclusion:Early surgery changed the natural evolution of Perthes disease. Early surgical treatment shortens the fragmentation period of Perthes disease, so that it enters the repair phase ear-lier, and has the opportunity to skip the late fragmentation period and change its natural course. After healing, the morphological change of the proximal femur is closer to normal.

Risk factors for avascular necorosis after closed reduction of developmental dysplasia of the hips / 中华骨科杂志

Objective:To analyze the risk factors of avascular necrosis (AVN) after closed reduction and spcia casting in treating developmental dysplaisa of the hip (DDH).Methods:The patients with DDH who received closed reduction in our department from January 2016 to December 2017 were retrospectively reviewed. The inclusion criteria included aged at reduction ≥6 months, achieving successful reduction, having complete data with more than 2 years follow-up. A total of 48 cases with 54 hips were included in the present study. Among them, there were 2 males and 46 females, 41 unilateral hips and 13 bilateral hips. The mean age at closed reduction was 16.4±3.8 months (range 6-24 months). The mean follow-up duration was 2.9±1.8 years (range 2.3-4.1 years). Closed reduction was conducted under general anesthesia followed with a spcia cast immobilization. The abduction angle of the cast was recorded. The stability of reduction was evaluated by Ramsey safety zone. The maximum abduction and re-dislocation abduction were recorded. The quality of reduction was evaluated by the medial gap and femoral head coverage on intraoperative arthrography and post-reduction MRI. AVN was diagnosed according to Salter criteria. The risk factors of AVN were analyzed by univariate and binary logistic regression analysis.Results:AVN occurred in 12 hips (22.2%) of 54 hips. International Hip Dysplasia Institute (IHDI) grade and the difference between maximum abduction and cast abduction (Max-Cast abduction) were related to the occurrence of AVN in univariate analysis. The incidence of AVN in hips of IHDI grade 4 (42.9%, 9/21) was significantly higher than that in hips of IHDI grade 3 (9.7%, 3/31) (χ 2=6.007, P=0.018). However, the hips of IHDI grade 3 and 2 (0%, 0/2) presented a similar incidence of AVN (χ 2=0.000, P=1.000). The Max-Cast abduction was -0.7°±5.9° in the AVN group and 6.1°±7.6° in the AVN group ( t=2.125, P=0.038). Finally, IHDI grade ( OR=8.256, P=0.015) and Max-Cast abduction ( OR=0.832, P=0.047) were both independent factors of AVN in multivariate analysis. Conclusion:Most of the hips with AVN are IHDI grade 4 after closed reduction for DDH. The abduction angle in a spica cast could not be significantly related to the occurrence of AVN. However, the risk of AVN might be increased when the cast abduction is close to or beyond the maximum abduction. Safe abduction in the cast should be 5 to 10 degrees less than maximum abduction at least.

Feasibility study of correcting distal femoral valgus deformity with fixator-assisted plating technique in adolescent / 中华骨科杂志

Objective:Comparing with the external fixator technique, investigate the clinical effect of fixator-assisted plating technique for treatment distal femoral valgus deformity in adolescent.Methods:A retrospective analysis of the relevant data of 22 patients (25 limbs) with acute correction of distal femoral valgus deformities from July 2015 to June 2019, according to the difference of the final fixation, they were divided two groups. The fixator-assisted plating group, including 8 patients (9 limbs), 5 boys and 3 girls, 5 left and 2 right, 1 bilateral, the physis were closed in 4 cases and opened in 4 cases, age 14.04±1.99 years (11.7-18 years). The external fixator group, including 14 patients (16 limbs), 6 boys and 8 girls, 8 left and 4 right, 2 bilateral, the physis were closed in 9 cases and opened in 5 cases, age 13.33±1.88 years (10.1-16.5 years). Measuring the mechanical axis deviation (MAD) and the mechanical lateral distal femur angle (mLDFA) in full length standing AP view X-ray of the lower limb pre and post operation. Recording the changed of limb length discrepancy (LLD) before and after surgery and the knee range of motion at 6 weeks, 3 months, 6 months and the last follow up post operation. The Kolcaba comfort status scale was used to evaluate the comfort of two groups at 2 weeks, 6 weeks, 3 months, 6 months and the last follow up. Meanwhile recorded the healing time of osteotomy sites and the complications.Results:The difference in general information between the two groups was not statistically significant. The fixator-assisted plating group followed up mean 26 months (range, 12-40 months), the healing time were 4.00±0.66 months, the mLDFA mean 73.33°±4.12° before surgery and 87.89°±1.69° after surgery and there was significant difference ( t=10.582, P<0.05). The external fixator group followed up mean 36 months (range, 22-42 months), the healing time were 4.00±0.66 months, the mLDFA mean 73.31°±3.95° before surgery and 87.31°±1.54° after surgery and there was significant difference ( t=14.118, P<0.05). The MAD were in the normal range in all patients after surgery, and there were no significant difference about healing time of the osteotomy sites and postoperative mLDFA between the two groups ( t=1.514, P=0.150; t=0.845, P=0.411). Comparing with the knee function, the fixator-assisted plating group was better at 6 weeks, 3 months, 6 months after surgery but there was no difference at the last follow up. Also, the fixator-assisted plating group felt more comfortable at 2 weeks, 6 weeks, 3 months, 6 months and there was no difference at the last follow up. All the patients with external fixator have mild pin sites infection and there were no obvious complications in patients with plate. Conclusion:The fixator-assisted plating technique can accurately correct the valgus deformity with satisfactory healing of the osteotomy in distal femoral compare with the external fixator technique, but the patients feel more comfortable and the knee joint function recovers faster and no risk of pin site infection, the clinical results was satisfactory with fewer complication.