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Hollow architecture and spinel heterogeneous interface strategy provides a novel approach to achieve high-performance cathode materials.

The doping effects of transition metals with various numbers of d electrons on Li2MnO3 are different. The summary of variation of the charge compensation mechanism facilitates the design of Li-rich cathodes.

Concurrent dislocation of the distal radiulnar joint of the proximal elbow and proximal radius fracture with rotatory noose injury medial to the ulnar tuberosity is an extremely rare case. No such injury has been reported in the domestic or international literature. The injury we report is similar to that of the proximal fibula of the ankle locked behind the tibial tuberosity, namely Bosworth's injury. We report a case of 36 male elbow proximal distal radial ulnar radial ulnar joint rotation joints and proximal radial fracture and dislocation bowstring in ulna nodule inside, in the rapid and timely accurate diagnosis under the emergency line open reduction and accurate judgment and treatment of this injury is challenging, early diagnosis and timely treatment can get the best curative effect.

AIMD simulations are performed to understand the structural, thermodynamic and thermophysical properties of disordered Li–Ga–Sn alloys formed in the initial stage of lithiation of liquid Ga91.6Sn8.4.

The doping of Cr, Mo and W enhances the electrochemical activity of Li2MnO3via different charge compensation mechanisms. A summary of the variations of charge compensation mechanisms facilitates the rapid design of Li-rich cathodes.

Reducing the loading of noble Pt-based catalyst is vital for the commercialization of proton exchange membrane fuel cell (PEMFC). However, severe mass transfer polarization loss resulting in fuel cell performance decline will be encountered in ultra-low Pt PEMFC. In this work, mild oxidized multiwalled carbon nanotubes (mMWCNT) were adopted to construct the catalyst layer, and by varying the loading of carbon nanotubes, the catalyst layer structure was optimized. A high peak power density of 1.23 W·cm−2 for the MEA with mMWCNT was obtained at an ultra-low loading of 120 μg·cm−2 Pt/PtRu (both cathode and anode), which was 44.7% higher than that of MEA without mMWCNT. Better catalyst dispersion, low charge transfer resistance, more porous structure and high hydrophobicity of catalyst layer were ascribed for the reasons of the performance improvement.

Objective To compare the clinical efficacy of percutaneous minimally invasive reduction combined with external fixation and a tarsal sinus approach to treat Sanders type II and III intra‐articular calcaneal fractures. Methods The clinical data of 64 patients with Sanders type II and III calcaneal fractures admitted to our hospital from January 2010 to January 2016 were retrospectively analyzed; data includedage, sex, body mass index. According to the surgical method, they were divided into the percutaneous minimally invasive reduction with internal and external fixation group (30 cases) and the tarsal sinus approach group (34 cases).The two groups of patients were compared in terms of the time tosurgery, length of hospital stay, intraoperative blood loss, operative duration, complications, radiographic features, including the heel bone length, width, height, Bohlerangle, Gissane angle, and calcaneal varus angle, and clinical efficacy indicators, including the American Orthopedic Foot and Ankle Society (AOFAS) score, the visual analog scale (VAS) pain score, health survey profile (SF‐36) score and Maryland ankle function score. Results Patients in both groups were followed up for 12 to 50 months, with an average of 24.8 months.Bony union was achieved in all cases. The time to surgery, length of hospitalstay, intraoperative blood loss and incidence of incision‐related complications were significantly lower in the percutaneous minimally invasive medial external fixation group than in the tarsal sinus group (P 0.05). As measures of clinical efficacy, the AOFAS, VAS, SF‐36 and Maryland scores were 85.28 ± 8.21, 0.84 ± 1.21, 82.95 ± 3.25 and 83.56 ± 3.32, respectively, at the last follow‐up in the percutaneous minimally invasive medial external fixation group and 83.32 ± 7.69, 1.85 ± 1.32, 80.71 ± 5.42, and 81.85 ± 2.41 in the tarsal sinus group, respectively, with no significant differences between the two groups (P > 0.05). Conclusion Under the condition of a good command of surgical indications and surgical skills, the use of plastic calcaneal forceps for percutaneous minimally invasive reduction combined with medial external fixation for the treatment of Sanders type II and III intra‐articular calcaneal fractures can achieve similar clinical effects as the tarsal sinus approach. However, the use of plastic calcaneal forceps for percutaneous minimally invasive reduction combined with internal and external fixation has advantages, such as fewer complications, less bloodloss, and a shorter operation, and thus has good safety and is worthy of clinical promotion., The anatomical structure of the calcaneus was restored by applying traction and extrusion with calcaneus‐shaping forceps. On axial X‐ray, 4 nails were arranged from the subtalar joint to the calcaneal tuberosity in different planes to provide fracture surface support. Two Kirschner wires drilled from the posterior tuberosity were fixed in the talus and cuboid to correct and control calcaneal varus. On lateral X‐ray near the Gissane angle, three nails were drilled in a zigzag arrangement perpendicular to the fracture line and the lateral wall of the calcaneus. The three nails were drilled almost in an equilateral triangle or at an angle of 60 degrees to maintain the fixed fractured end. The first nail near the bottom of the calcaneal tubercle was drilled vertically to the fracture line to avoid calcaneal widening. Two Kirschner wires, one high and one low, were fixed in the talus and cuboid at an angle of approximately 45 degrees to prevent height collapse and calcaneal shortening.

MnO, as a promising anode for lithium-ion batteries, is easy to form high-valence manganese oxides during the battery operation, causing a continuous capacity increase and hindering practical appli...

To investigate the clinical efficacy of accelerated rehabilitation surgery for the treatment of Gustilo type IIIA/B open tibiofibular fracture with emergency stage I debridement, internal fracture fixation, bone grafting, coverage of the wound surface with a muscle flap combined with vacuum sealing drainage (VSD), and internal and lateral leg reduction.A retrospective analysis was performed on the clinical data of 15 patients with Gustilo type IIIA/B open tibiofibular fracture who were admitted to the Affiliated Zhongshan Hospital of Dalian University from January 2015 to December 2018. There were 12 males and 3 females. The patients ranged in age from 20 to 62 years, with an average of 39.5 years. After admission, the patients underwent stage I emergency debridement (including exploration and repair of nerves and tendons), open reduction and internal fixation of the tibia and fibula, iliac bone grafting, muscle flap and VSD coverage of the bone defect, complete tensioning of the calf inside and outside, tibia-sparing incision before healing, and stage II free skin grafting. Patients were followed up periodically to observe muscle flap survival, fracture healing time, length of hospitalization, wound healing time, delayed union, bone nonunion, osteomyelitis and other complications. At the last follow-up, the Johner-Wruhs criteria were used to evaluate the rate of good functional recovery from tibial shaft fracture, fracture healing quality was evaluated by the Merchant score, and limb function was evaluated by the LEFS.All 15 cases were followed up for 12-32 months, with an average of 22.8 months. All the fractures healed; the range of healing time was 14-30 weeks (mean 18.5 weeks). The length of hospitalization was 25.1 ± 7.6 days, and wound healing took 12.2 ± 2.0 days. None of the patients had complications such as osteomyelitis infection. When the Johner-Wruhs evaluation criteria for functional recovery from tibial shaft fracture were applied at the last follow-up, the outcomes were as follows: excellent in 13 cases, good in 1 case and fair in 1 case, for an excellent and good rate of 93.3%. When fracture healing was evaluated according to the Merchant scoring standard, the outcomes were as follows: excellent in 12 cases, good in 1 case, fair in 1 case, and poor in 1 case, for an excellent and good rate of 86.7%. The mean LEFS score of the affected limb at the last follow-up was 70 (59-80).For Gustilo type IIIA/B open tibiofibular fractures, emergency stage I debridement, internal fixation of the fracture, bone grafting, coverage of the wound with a muscle flap, complete tensioning of the calf inside and outside, and application of VSD can improve the repair of leg soft-tissue defects, shorten hospitalization time, promote fracture healing, and effectively reduce infection and complications related to bone exposure. More importantly, this treatment protocol provides effective wound repair, guarantees the recovery of limb function, significantly speeds up recovery, and improve patients' quality of life.

Spinel LiMn$_{2}$O$_{4}$ has attracted wide attention due to its advantages of a high-voltage plateau, good capacity, environmental friendliness, and low cost. Due to different experimental synthesis methods and conditions, there are many intrinsic point defects in LiMn$_{2}$O$_{4}$. By means of first-principles calculations based on a reasonable magnetic configuration, we studied the formation energies, local structures, and charge compensation mechanism of intrinsic point defects in LiMn$_{2}$O$_{4}$. The formation energies of defects under the assumed O-rich equilibrium conditions were examined. It was found that O, Li, and Mn vacancies, Mn and Li antisites, and Li interstitial could appear in the lattice at some equilibrium conditions, but Mn interstitial is hard to form. The charge was compensated mainly by adjusting the oxidation state of Mn around the defect, except for the defects at the 8a Wyckoff site. The binding energies between point defects were calculated to shed light on the clustering of point defects. Furthermore, the diffusion of Li ions around the defects was discussed. Cation antisites led to a decrease of the Li diffusion barrier but O vacancy caused an increase of the barrier. This study provides theoretical support for understanding point defects in spinel LiMn$_{2}$O$_{4}$.

Drug delivery systems based on genetically engineered oncolytic bacteria have properties that cannot be achieved by traditional therapeutic interventions. Thus, they have attracted considerable attention in cancer therapies. Attenuated bacteria can specifically target and actively penetrate tumor tissues and play an important role in cancer suppression as the "factories" of diverse anticancer drugs. Over the past decades, several bacterial strains including Salmonella and Clostridium have been shown to effectively retard tumor growth and metastasis, and thus improve survival in preclinical models or clinical cases. In this review, we summarize the unique properties of oncolytic bacteria and their anticancer mechanisms and highlight the particular advantages compared with traditional strategies. With the current research progress, we demonstrate the potential value of oncolytic bacteria-based drug delivery systems for clinical applications. In addition, we discuss novel strategies of cancer therapies integrating oncolytic bacteria, which will provide hope to further improve and standardize the current regimens in the near future.

MXene based materials are theoretical predicted as one of the most promising cathode materials for lithium-oxygen batteries due to their unique electronic structure, large surface area and lattice matching with Li2O2, but still be impeded by the lack of high electrocatalytic performance, inhomogeneous surface condition and poor understanding for reaction kinetics and mechanism during ORR/OER process. In the present work, we fabricated the Ti2C MXene decorated with -O and -F multifunctional groups. DFT calculations revealed that the Ti2CO2 surface provided a high efficient single electron reaction pathway for the adsorption-nucleation-decomposition process of Li2O2 acting as the main catalytic sites compared to the Ti2CF2 surface, meanwhile, the bare Ti2C surface degraded the catalytic capability of Ti2C MXene due to the strong chemical binding with Li2O2. Further, the inhomogeneous surface condition was supposed to promote the polarized nucleation and growth of discharge products to form the porous structure from spatial-direction accumulated nanoflakes, which can provide an efficient pathway for mass transfer. As a result, the T2C MXene cathode exhibited excellent performance in terms of superior capacity and long cycle stability. The present work provides intrinsic insights toward the catalytic mechanism and reaction kinetics of Ti2C MXene decorated with multifunctional groups, which contributes to the rational design of high performance MXene based materials in Li-O2 batteries.

There has been a “trade-off” between ion exchange capacity (IEC) and mechanical properties in anion exchange membranes. Thinking out of the box, high ion conductivity was realized with only a small...

For high-performance anion exchange membrane fuel cells (AEMFCs), the anion exchange membrane (AEMs) should be as thin as possible to reduce the ohmic resistance. However, the mechanical stability of ultrathin AEMs cannot be guaranteed, as well as a huge risk of gas (H

Heterogeneous atoms substitution is an efficient method for promoting Li

Searching for an efficient HER catalyst in alkaline media still faces big challenges due to the sluggish water splitting kinetics as well as the hindrance of the hydrogen adsorption–desorption process. Based on this, herein, we fabricated a bamboo leaves-like amorphous FeOx (x = 1, 1.5) coated Cu3P with outstanding HER performance in alkaline media for the first time. FeOx·H2O was synthesized by the reducibility of glycol and the oxidability of soluble O2, and the bamboo leaves-like structure was induced by solvent molecule selective adsorption simultaneously. The binder-free FeOx coated Cu3P@Cu was fabricated as the catalyst for HER in 1 M KOH, which demonstrated a quite low overpotential of 48 mV at 10 mA cm−2 and was even better than that of Pt/C catalyst at a large current density. This work provided a strategy to fabricate a high-performance copper-based HER electro-catalyst.

Purpose MicroRNA-761 (miR-761) has been reported to be deregulated in many types of human cancers and play important roles in cancer genesis and progression. However, the biological roles of miR-761 in osteosarcoma (OS) and the underlying mechanisms remain largely unknown. Methods The expression of miR-761 in OS tissues and cell lines was analyzed using RT-qPCR. A series of gain-of-function tests were performed, and status of malignancy was evaluated on basis of proliferation, migration, invasion, and apoptosis using different assays to determine the regulatory roles of miR-761 in OS cells in vivo and in vitro. Notably, the mechanisms underlying the action of miR-761 in the pathogenesis of OS were investigated using bioinformatic analysis, luciferase reporter assay, RT-qPCR and Western blotting. Results The results showed that miR-761 expression was decreased in OS tissues and cell lines and is closely correlated with clinical stage and distant metastasis in OS patients. Patients with OS having low miR-761 expression showed worse prognosis compared to OS patients with high miR-761 expression. Restoring the miR-761 expression level decreased OS cell proliferation, migration, and invasion in vitro; promoted cell apoptosis in vitro; and impaired tumor growth in vivo. In addition, fibroblast growth factor receptor 1 (FGFR1) was found as a direct target gene of miR-761 in OS cells. Furthermore, silencing FGFR1 expression stimulated the tumor-suppressing roles of miR-761 upregulation in OS cells, whereas the activity of miR-761 overexpression in OS cells was abolished by the restoration of FGFR1 expression. Moreover, restoration of miR-761 expression deactivated the PI3K/Akt pathway in vitro and in vivo. Conclusion These results suggest that miR-761 plays anti-cancer roles in OS by directly targeting FGFR1 and deactivating the PI3K/Akt pathway. The newly identified miR-761/FGFR1/PI3K/Akt pathway partially illustrates the mechanism of OS pathogenesis and presents a novel candidate therapeutic target for antitumor therapy.

Cu6Sn5 is a promising alternative material for commercial anode in lithium ion batteries. In this study, the thermal stability of ternary compounds in the Cu-Li-Sn system and equilibrium phase transition of Cu6Sn5 upon charge-discharge reaction are investigated by means of first-principles calculations and key experiments. The ternary phase diagram for the Cu-Li-Sn system at 0 K constructed by first-principles calculations exhibits that CuLi2Sn2, CuLi2Sn and Cu2LiSn are thermodynamically stable, but Cu6Li3Sn4 is thermodynamically metastable. In addition, calculated equilibrium reaction path and voltage curve of Cu6Sn5 electrode suggest that CuLi2Sn2 and Cu2LiSn firstly form before the well-known CuLi2Sn appears during lithiation. Vibrational free energy contribution is introduced to study thermal stability of ternary phases, which predicts that Cu6Li3Sn4 is thermodynamically stable above 148 °C. In order to verify our calculations, phase equilibria of eleven ternary alloys at 120 and 180 °C are investigated by means of X-ray diffraction, scanning electron microscopy and electron probe microanalyses. It shows that Cu6Li3Sn4 can decompose between 180 and 120 °C, which is consistent with our predictions in calculations. Thus, our study suggests that Cu6Li3Sn4 is metastable at room temperature and CuLi2Sn2, CuLi2Sn and Cu2LiSn can form during the electrochemical lithiation of Cu6Sn5 electrode.

We have employed ab initio molecular dynamics simulations to study the oxidation behavior of TiAlN hard coatings as a function of Al content and temperature. Results show that for TiAlN with a low Al content (Ti0.75Al0.25N), Ti atoms can always bond with O atoms, while Al atoms bond with O only at a higher temperature. For Ti0.5Al0.5N, both Al and Ti can bond with O atoms, irrespective of temperature. Through analyzing the displacement height of O-bonded metal atoms, we suggest that titanium oxide nucleates at the outermost layer of Ti0.75Al0.25N while the outermost layer after Ti0.5Al0.5N is exposed to oxygen is aluminum oxide. Our simulation results predict, in agreement with experiment, that Ti0.5Al0.5N has superior oxidation resistance in comparison with Ti0.75Al0.25N. This study provides an atomistic insight to the initial stage of the oxidation process, which is else difficult to observe experimentally.

Lithium-rich layered Li

As a promising hydrogen storage material, sodium borohydride (NaBH4) exhibits superior stability in alkaline solutions and delivers 10.8 wt.% theoretical hydrogen storage capacity. Nevertheless, its hydrolysis reaction at room temperature must be activated and accelerated by adding an effective catalyst. In this study, we synthesize Co nanoparticles supported on bagasse-derived porous carbon (Co@xPC) for catalytic hydrolytic dehydrogenation of NaBH4. According to the experimental results, Co nanoparticles with uniform particle size and high dispersion are successfully supported on porous carbon to achieve a Co@150PC catalyst. It exhibits particularly high activity of hydrogen generation with the optimal hydrogen production rate of 11086.4 mLH2∙min−1∙gCo−1 and low activation energy (Ea) of 31.25 kJ mol−1. The calculation results based on density functional theory (DFT) indicate that the Co@xPC structure is conducive to the dissociation of [BH4]−, which effectively enhances the hydrolysis efficiency of NaBH4. Moreover, Co@150PC presents an excellent durability, retaining 72.0% of the initial catalyst activity after 15 cycling tests. Moreover, we also explored the degradation mechanism of catalyst performance.

The rational design of a catalytic layer in a membrane-electrode assembly is the key to achieve high performances from proton exchange membrane fuel cells (PEMFCs). Herein, inspired by the neural-network structure of the brain, we constructed a bionic catalytic network for the oxygen reduction reaction (ORR), via setting up Pt-organic ligands–Co2+–organic ligands–Pt connections and then thermally transforming them into a metal-organic-framework (MOF)-like matrix in which hollow PtCo alloy nanoparticles (NPs) with an average particle size of 4.4 nm are bridged together by carbon nanotubes (PtCo@CNTs-MOF). The bionic catalytic network provides highly efficient linkages of various species-transport channels to active sites; as a result, an order of magnitude improvement is achieved in mass transfer efficiency as compared to the traditional Pt/C catalytic layer. Besides, the hollow PtCo alloy derived from Pt NPs shows a high initial mass activity of 852 mA mgPt−1 @ 0.90 V and an undetectable decay in an accelerated aging test. Accordingly, a remarkable Pt utilization efficiency of 58 mgPt kW−1 in the fuel cell cathode and 98 mgPt kW−1 in both the anode and cathode was eventually achieved, respectively. The latter is almost 3 times higher than that of the traditional catalytic layer. Moreover, no decay was detected during continuous operation at 1 A cm−2 for 130 hours from the bionic catalytic network based fuel cell. This strategy offers a new concept for designing an ultra-low Pt loading yet highly active and durable catalytic layer for fuel cell applications and beyond.