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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.

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.

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.

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.

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...

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

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.

The molybdenum dioxide (MoO2)–molybdenum carbide (Mo2C) heterostructures were built by in situ forming the (100) plane of Mo2C nanoparticles along the (101) plane of MoO2 nanoparticles and were simultaneously anchored on a 3D holey carbon substrate via optimized annealing of the bio-inspired ammonium molybdate tetrahydrate-agar gel. Both experimental results and theoretical simulations demonstrated the important roles of wide interfaces between MoO2 and Mo2C in improving the electrochemical performance of MoO2-based electrodes. These uniquely prepared MoO2/Mo2C/C electrodes delivered a capacity of 845.2 mA h g−1 at 0.1 A g−1 after 200 cycles, with a capacity change rate of 2.3%, overcoming the key obstacle for commercial application of transition metal oxides caused by capacity changes during the cycling process. Meanwhile, the electrodes displayed ultrastable long cycling performance with a capacity of 507.3 mA h g−1 at a high current density of 1.0 A g−1 after 2400 cycles, still far higher than the theoretical capacity of carbon materials. Both a local in-built driving force in the electrodes and synergistically induced more efficient mass transport across the interface were predicted by the Density Functional Theory (DFT) and Density of States (DOS) calculations from the formed interfacial electric field, yielding the fast reaction kinetics and outstanding lithium storage ability. This work highlights an efficient strategy to obtain ultrastable long cycling performance and also excellent electrochemical performance of MoO2-based materials and other transition metal oxides as anodes for lithium ion batteries. In addition, the full batteries based on MoO2/Mo2C/C anodes and a commercial LiCoO2 cathode present stable cycling performance.

Using first-principles calculations based on density functional theory, we systematically study the adsorption and diffusion behaviors of single oxygen (O) atom on the (0 0 1) surfaces of TiN, ZrN and HfN nitride coatings. The top of N site (top(N)) is the most energetic favorable site for O atom and followed by the hollow site for all the three nitrides. O atom tends to diffuse on the (0 0 1) surfaces of the nitrides from the top of transition metal top(TM) sites to a neighboring top(TM) sites by avoiding N sites. The adsorption of O on ZrN and HfN is more stable than that on TiN. Our findings could explain the experimental phenomenon that the oxide thickness of TiN is smaller than that of ZrN under the same oxidation conditions.

Based on 18 bulk diffusion couples, the composition-dependent interdiffusion coefficients in the fcc Co-V-Mo alloys at 1273, 1373 and 1473 K were obtained from the intersection points of the diffusion couples by means of EPMA technique coupled with the Whittle and Green method. With the experimentally determined interdiffusion coefficients and the critically reviewed experimental diffusivities available in the literature, the atomic mobilities of fcc Co-V-Mo alloys were assessed by means of Diffusion Controlled Transformation (DICTRA) software. The quality of the assessed atomic mobilities was confirmed by the comprehensive comparisons between various DICTRA-calculated diffusion behaviors and the experimental ones, including concentration profiles and diffusion paths.

The Pt-based alloys with Pt-skin or Pt-rich surface own significant structural advantages for a range of electrocatalytic reactions. Herein, we give a minireview for such catalysts, which covers a brief background introduction, the mechanisms for the activity enhancements derived from the special Pt-skin structures, the very recent advances on the preparation routes and applications of the catalysts in various electrochemical reactions, and a future perspective. Indeed the Pt-skin structured catalysts have shown great promising which in the future, may provide more opportunities for enhancing electrocatalytic performance at the molecular level.

International audience; Structural feature of equiaxed Guinier-Preston zones with the diameter of ∼2 nm in an Al-Mg-Si-Cu alloy has been systematically investigated by three-dimensional atom probe analyses, high-resolution electron microscopy and first-principles calculations. The results suggest that Si and Mg planes alternate along [001]Al with Cu atoms diversely substituting for some Si sites. An fcc-based Mg1(Si,Cu)1 model was then proposed for the first time, with expanded a, b and compressed c lattice parameters compared to Al. Meanwhile the structural evolution of Mg1(Si,Cu)1 → (Mg,Cu)1(Si,Cu)1 → β″-(Mg,Cu)1Mg4(Al,Cu)2Si4 is suggested.

In αI integrins, including leukocyte function–associated antigen 1 (LFA-1), ligand-binding function is delegated to the αI domain, requiring extra steps in the relay of signals that activate ligand binding and coordinate it with cytoplasmic signals. Crystal structures reveal great variation in orientation between the αI domain and the remainder of the integrin head. Here, we investigated the mechanisms involved in signal relay to the αI domain, including whether binding of the ligand intercellular adhesion molecule-1 (ICAM-1) to the αI domain is linked to headpiece opening and engenders a preferred αI domain orientation. Using small-angle X-ray scattering and negative-stain EM, we define structures of ICAM-1, LFA-1, and their complex, and the effect of activation by Mn(2+). Headpiece opening was substantially stabilized by substitution of Mg(2+) with Mn(2+) and became complete upon ICAM-1 addition. These agents stabilized αI-headpiece orientation, resulting in a well-defined orientation of ICAM-1 such that its tandem Ig-like domains pointed in the opposite direction from the β-subunit leg of LFA-1. Mutations in the integrin βI domain α1/α1′ helix stabilizing either the open or the closed βI-domain conformation indicated that α1/α1′ helix movements are linked to ICAM-1 binding by the αI domain and to the extended-open conformation of the ectodomain. The LFA-1–ICAM-1 orientation described here with ICAM-1 pointing anti-parallel to the LFA-1 β-subunit leg is the same orientation that would be stabilized by tensile force transmitted between the ligand and the actin cytoskeleton and is consistent with the cytoskeletal force model of integrin activation.

Heterogeneous atoms substitution is an efficient method for promoting Li+ storage of transition metal oxides. Herein, a series of Fe-substituted MnO solid solutions with different Fe contents are synthesized by a feasible solid-phase method. The synergistic effects between heterogeneous atoms and rich vacancies are synchronously obtained, which hold distinctive electronic structures and substantial active sites. When optimized Mn0.55 Fe0.45 O solid solution as anodes for lithium-ion batteries, pre-prepared electrodes exhibit reversible lithium storage of 1286.9 mAh g-1 at 1 A g -1 after 400 cycles and even 628.1 mAh g-1 at 2 A g-1 after 1000 cycles. The LiCoO2 //Mn0.55 Fe0.45 O full cells are assembled, achieving the reversible capacity of 130.2 and 111.3 mAh g-1 after 150 cycles at 0.1 and 0.2 A g-1 , respectively. Density functional theory calculations also authenticate that the electrochemical activity can be markedly boosted by the heterogeneous atoms substituted Mn1-x Fex O solid solution.

The transition-metal compounds (MX) have gained wide attention as hydrogen evolution reaction (HER) electrocatalysts; however, the interaction between the non-metallic atom (X) and the metal atom (M) in MX, and the role of X in the enhanced catalytic activity of MX, are still ambiguous. In this work, we constructed a simple model [X/Ni(100)] to decipher the contribution of X towards enhancing the catalytic activity of NiX, which allows us to accurately predict the trend in HER catalytic activity of NiX based on the easily accessible physico-chemical characteristics of X. Theoretical calculations showed that the electronegativity (χX) and the principle quantum number (nX) of X are two important descriptors for evaluating and predicting the HER catalytic activity of NiX catalysts effectively. X atoms in the VIA group can enhance the HER activity of X/Ni(100) more significantly than those in the second period due to the large χX or nX. At a relatively low X coverage, the S/Ni(100) possesses the best HER activity among all of the discussed X/Ni(100) models, and the optimum surface S : Ni atomic ratio is about 22–33%. Further experiments demonstrated that the Ni–Ni3S2 catalyst with a surface S : Ni atomic ratio of 28.9% exhibits the best catalytic activity and lowest charge transfer resistance. The trend in catalytic activity of NiX with differing X offers a new possible strategy to exploit MX materials and design new active catalysts rationally.

Sb and Sb-containing compounds have been attracting a great interest as promising alternative materials for commercial anodes and liquid batteries. The Li-Sb system was studies experimentally by investigating 6 alloys with X-ray diffraction measurement, scanning electron microscopy and electron probe microanalyses. Two binary phases Li2Sb and Li3Sb were confirmed to be stable in this system. Two invariant reactions L→(Sb)+Li2Sb and L+Li3Sb→Li2Sb were identified experimentally based on the microstructures of the as-cast alloys. The eutectic point was determined to be about 40 at% Li. The enthalpies of formation for Li2Sb, αLi3Sb and βLi3Sb at 0 K were calculated by means of density functional theory and the transition enthalpy between αLi3Sb and βLi3Sb was obtained. Then, the presently obtained results, combined with a critical review of literature data, were used to develop the thermodynamic description of the Li-Sb system by means of CALPHAD method. The liquid phase was treated as (Li, Li3Sb, Sb) using an associate model. The calculated phase diagram and thermodynamic properties can reproduce the available experimental data reasonably.

CoNiP nanosheet array catalysts were successfully prepared on three-dimensional (3D) graphene foam using hydrothermal synthesis. These catalysts were prepared using 3D Ni-graphene foam (Ni/GF), comprising nickel foam as the 'skeleton' and reduced graphene oxide as the 'skin'. This unique continuous modified 'skeleton/skin' structure ensure that the catalysts had a large surface area, excellent conductivity, and sufficient surface functional groups, which promoted

Quaternary ammonium (QA)-type polysulfone (PSf) anion exchange membranes (AEMs) with pendant carbonyl groups were synthesized by an environmentally friendly method. Low toxicity 3-chloro-2,2-dimethylpropionyl chloride (CDPC) was chosen as an electrophilic reagent to introduce chloroalkyl groups to PSf, instead of highly toxic chloromethyl methyl ether. The experimental conditions were carefully optimized to avoid the Friedel–Crafts alkylation side reaction on the chloroalkyl group. After quaternizing with trimethylamine (TMA), AEMs were prepared by solution casting. The obtained AEMs showed good ionic conductivity and mechanical stability. The alkaline stability of these AEMs was excellent; the AEMs can maintain 95% of their initial conductivity after immersion in a 1 M NaOH aqueous solution at 80 °C for 10 days. The reason for this outstanding alkaline stability was evaluated by NMR and density functional theory calculations. The most severe degradation pathway, the SN2 reaction, can be weakened by the competing reaction between OH− and carbonyl groups. The formed intermediate oxygen anion can decrease the possibility of SN2 by reducing the electro-static potential of the QA groups. Because of the reversibility of the reaction between OH− and carbonyl groups, QA groups can survive longer in strong alkaline conditions at high temperature. Also, the possibility of SN2 reaction on the aromatic polymer chain can be decreased because of the positive charge carrier, QA groups, which are not directly attached to benzyl groups. Hoffmann elimination can not happen because there was no hydrogen atom on the β-position of QA group. These structural advantages of the synthesized AEMs suggest another strategy that the potential for generalisation to other AEM systems and to improve the alkaline stability of QA-type AEMs.

Alloying is an effective method to improve mechanical properties of some compounds. The present work predicted an alloying strategy for improving fracture toughness of C15 NbCr2 Laves phase. The lattice parameters of C15 NbCr2-based ternary compounds with transition metal elements were calculated using first principles, revealing a relationship between lattice parameters and radii of transition metal elements. The atomic free volumes of a series of C15 NbCr2-based ternary compounds with transition elements were calculated and proposed as an indicator for a knowledge-based strategy for toughening enhancement of the C15 NbCr2 Laves phase. According to the presently calculated results, Re has the largest potential to improve fracture toughness of C15 NbCr2 Laves phase, since it has the largest atomic free volume, followed by Os, Ir, Tc, Ru, Rh, Cu, Pt and Mo.

Sn and Sn-based compounds have been attracting a great interest as promising alternative materials for commercial anodes in lithium ion batteries. In this study, the phase evolution of the Li-Sn system during the lithiated processes and the effect of the elastic-strain energies caused by volume change on the phase transition are investigated by means of first-principles calculations. Our calculated results demonstrate that the distorted Li 7 Sn 3 crystal tends to be formed in order to decrease the elastic-strain energy. In addition, our work indicates that the whole lithiated processes under the elastically constrained condition could be classified into two steps. The first step is the two-phase equilibrium process, in which the thermodynamic driving force is large enough to facilitate the phase transition and the plateau voltage could be established. The second step is considered to be the selective equilibrium, in which the thermodynamic driving force is not enough to facilitate the nucleation of the new equilibrium phase due to the elastically constrained conditions and the plateau voltage unformed. Besides, we find that in the Li 0.4 Sn matrix the nucleation of the αSn is more preferential than the βSn due to the effects of the elastic-strain energies.

Pugh’s criterion in terms of the bulk/shear modulus ratio ( B / G ) is widely used to distinguish the ductility and brittleness of metals, with the recommended B / G ratio of 1.75 for the boundary ratio between ductility and brittleness. The present first-principles calculations yield a B / G = 3.69 for the C15 Laves phase NbCr 2 , suggesting the ductility of NbCr 2 according to Pugh’s criterion. However, experiments indicate that NbCr 2 is a brittle phase at room temperature with the fracture toughness of 1.0–1.4 MPa m 1/2 . NbCr 2 is hence a compound with its ductile and brittle behavior beyond Pugh’s criterion, and this finding also validates for other Laves phases and compounds. New insight into Pugh’s B / G criterion is also discussed.

Hydrothermally carbonized chitosan has been successfully used as a carbon source for the preparation of highly porous carbons via chemical activation. The porous carbons with different nitrogen contents (0.56–6.53 wt%) have high surface area (1362–3009 m 2 g −1 ) and large pore volume (0.670–1.497 cm 3 g −1 ). These properties can be varied from modifying the activation parameters ( i.e. , amount of activation agent and activation temperature). We observed hydrogen storage capacity of up to 2.71 wt% at 77 K and 1 bar, and 6.77 wt% at 20 bar, for PC-2-800 porous carbons. This result indicates that the hydrogen uptake of porous carbons mainly depends on the high micropore surface area related to optimum pore size. Furthermore, one found that high N-doping is beneficial for hydrogen storage at low pressure but it is detrimental at high pressure according to the analysis of hydrogen uptake isotherms.