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Adding gentamicin to silk fibroin enhances both the antibacterial performance and degradation rate of silk-based materials. The increased material degradation rate can affect the strength of early internal fixation, resulting in internal fixation failure. This study sought to adjust the gentamicin concentration to control the material degradation rate, thereby better meeting clinical application requirements. The in vitro degradation, water absorption rate, and expansion rate of silk-based materials containing different gentamicin concentrations were studied. A gentamicin-loaded silk-based screw was implanted into the femurs of New Zealand rabbits. Micro-computed tomography was used to measure the screw diameter, which was then used to calculate the degradation rate. The specimens were stained with hematoxylin and eosin and Masson’s trichrome. The in vitro results revealed increasing material degradation rates with increasing gentamicin concentration but no significant differences in water absorption rates with different gentamicin concentrations. The degradation rates of gentamicin-loaded (4 mg/g) silk-based rod-like materials were approximately 11.08% at three months in vitro and 9.4% in the animal experiment. The time for complete degradation was predicted from the fitting curve to be approximately 16 months. No inflammatory hyperplasia was observed in bone or soft tissue. The degradation and biocompatibility of the material containing 4 mg/g gentamicin meet clinical application requirements, and previous experimental results demonstrate good antibacterial performance of materials containing this gentamicin concentration.

Profiting from the elaborate design, the novel host materials combining advantages of the trapping ability (by V2O5) and catalytic activity (by VN) can significantly improve the cycle stability of Li–S batteries.

CuAgSe has been considered as a promising thermoelectric material because of its high mobility and low thermal conductivity. The superior performance of CuAgSe is closely related to its crystal structure and electric properties. In this work, the stabilities and electronic structures of different three CuAgSe subcells have been theoretically investigated using Vienna Ab initio Simulation Package (VASP) with DFT calculations. We found that the different occupations of copper atoms would affect the stability and electronic structures of CuAgSe subcells. The various directions of Cu-Se chain in neighbor layers will result in different stabilities and electronic properties.

In order to have a better understanding of the electronic structures and physical properties of Cu2-δX (X = Se, S, Te) copper chalcogenides. First principles were performed to calculate the chemical shift, band structure, and electron density of states of Cu2-δX (X = Se, S, Te). By comparing our calculation results with previous experimental works, we found that the predicted electronic structures of Cu2Se, Cu2Te and Cu2S transform from semimetal to semiconductor after adding on-site Coulomb U, which reflects the real properties of the materials. By using (Density Functional Theory) DFT + U method, the calculation result is close to the real electronic structure. The calculation result of chemical shift of adding U does not reach the ideal expectation, and the reason is not clear at present. In this paper, the theoretical electronic structures of Cu2Se, Cu2Te and Cu2S are better calculated by DFT + U method and compared with the actual properties. The effect of Cu-s electron on the chemical shift is understood, and a theoretical result of the chemical shift is calculated, which provides a powerful reference for the subsequent research and understanding of the electronic structure and physical properties of the compounds with S groups of Cu.

The tectonic evolution of the southwestern Yangtze Block during the Early Neoproterozoic period is still controversial because of the limited quantities of 1 000–860 Ma magmatic rocks. In this study, our new LA-ICP-MS zircon U-Pb dating results demonstrate that the Yanbian granodiorites in the southwest Yangtze Block were emplaced at 894.6±7.4 Ma, representing the product of an 894 Ma magmatism. The Yanbian granodiorites are metaluminous to weak peraluminous with A/CNK values of 0.8–1.1, resembling I-type granitoids. They are characterized by right-inclined REE patterns with moderate to insignificant negative Eu anomalies (δEu=0.6–0.9). Their primitive mantle-normalized trace element patterns are characterized by depletion of Nb, Ta and Ti and weakly enrichment of Th. Considering the positive whole-rock eNd(t) (+5.8 to +6.8), we propose that these granodiorites originated from the partial melting of juvenile mafic lower crust. The Yanbian I-type granitoids have low Y and Nb contents similar to volcanic arc igneous rocks in the Y-Nb plot for tectonic discrimination. In conclusion, Early Neoproterozoic Yanbian granodiorites have generated in a compression setting in an active continental margin. Together with previous studies from the southwestern Yangtze Block, we suggest that the 894 Ma subduction-related Yanbian granodiorites represent the early stage of subduction at the southwestern margin of the Yangtze Block.

Lithium-sulfur (Li-S) batteries show great potential in future electric transportation and large-scale grid storage applications because of their attractive theoretical energy density (2600 W h kg

This work aims to freely translate an input face to an aging face with robust identity preservation, satisfying aging effect and authentic visual appearance. Witnessing the success of GAN in image synthesis, researchers employ GAN to address the problem of face aging synthesis. However, most GAN-based methods hold that the aging changing of all facial regions is equal, which ignores the fact that different facial regions have distinct aging speeds and aging patterns. To this end, we propose a novel Conditioned-Attention Normalization GAN (CAN-GAN) for age synthesis by leveraging the aging difference between two age groups to capture facial aging regions with different attention factors. In particular, a new Conditioned-Attention Normalization (CAN) layer is designed to enhance the aging-relevant information of face, while smoothing the aging-irrelevant information of face by attention map. Since different facial attributes contribute to the discrimination of age groups with divers degrees, we further present a Contribution-Aware Age Classifier (CAAC) that finely measures the importance of face vector’s elements in terms of the age classification. Qualitative and quantitative experiments on several commonly-used datasets show the advance of CAN-GAN compared with the other competitive methods.

In traditional dual-ion systems, the cathode usually is employed as anion-storage materials. Herein, we propose a new dual-ion hybrid supercapacitor with reverse anion/cation-storage mechanism, consisting of a mesoporous (MPs) VN anode as a pivotal anion-storage material and K

To evaluate the operating range and morphology of the surgical safe zone for oblique lumbar interbody fusion (OLIF). Twenty embalmed full-torso cadaveric specimens were dissected. The oblique corridor and the distance between adjacent lumbar arteries were measured in a static state and with psoas major retraction. The morphology and size of the safe zone for OLIF and the location of the lumbar sympathetic trunk were also recorded. The oblique corridor of the L1-L5 segments was significantly greater in the retracted state than in the static state (p < 0.05). With psoas major retraction, the distances between adjacent lumbar arteries at L1-4 were significantly greater (p < 0.05) than those in the static state. The lumbar sympathetic trunk is just located in the safe zone and travels downward adjacent to the psoas major. The shape of the safe zone for OLIF was approximately an oblique upward parallelogram at L1/2 and L2/3, an isosceles trapezoid at L3/4, and an irregular quadrangle or triangle at L4/5. The safe zone for OLIF at L1/2, L2/3, and L3/4 was significantly larger during retraction than in the static state (p < 0.05). On the lateral side of the lumbar spine there is a natural surgical safe zone for OLIF, which can provide a sufficient operating space. The safe zone has a certain morphological pattern in L1-5 segments and psoas major retraction can significantly enlarge it.

A blastproof partition wall in civil air defense engineering is easily subjected to out-of-plane impact loads, such as object impacts, and structural collapse in peacetime. In this study, the pendulum impact test was carried out for the first time on six blastproof partition walls pasted with fiber-reinforced polymer (FRP). Using a method combining finite element simulation and experimental research, the influence of parameters such as the FRP type, layer number and width, and pendulum impact number on the impact resistance of the wall was systematically studied. The test results show that pasting FRP on the back of the blastproof partition wall can significantly improve the impact resistance and reduce the damage degree of the concrete. The impact recovery coefficient increased from 0.33 to 0.57, but with the increase in the number of impacts, large-rupture-strain FRP (LRS-FRP) can give full play to the advantages of a large tensile fracture strain and cooperate with the wall to deform, and the selection of FRP with a large tensile fracture strain is the key to resisting multiple impact loads. Finally, the experimental basis and an economical and reliable protection method are provided for the study of improving the impact resistance of the blastproof partition wall.

Hybrid supercapacitors (HSCs) with the characteristics of high energy density, long cycle life and without altering their power density need to be developed urgently. Herein, a novel dual-ion hybrid supercapacitors (DHSCs) with Ni(OH)

Structural layout scheme of dual rotor system with inter-shaft bearing plays an important role in reducing the bearing frame and structure weight of areo-engine. This kind of scheme is often used in the design of high thrust-weight ratio turbofan engine. However, the inter-shaft bearing will cause the direct interaction of the force and displacement between the high and low pressure rotor systems, contributing to the coupling of the dynamic characteristics of two rotor systems. The coupling may eventually lead to the failure of the rotor displacement control, loss of the robustness of the connection structure or excessive dynamic load of the bearing. The main purpose of this paper is to, firstly study and quantitatively evaluate the coupling characteristics of the dual rotor system, secondly obtain the correlation between the structural feature parameters such as the position of the inter-shaft bearing and the coupling vibration or interactive excitation characteristics of the system, finally propose the coupling vibration control method of dual rotor system. The dynamic model of dual rotor system with inter-shaft bearing is established. The modal frequencies and modes of dual rotor system with or without coupling are analyzed and compared. The results illustrate the complexity of coupled vibration of high pressure and low pressure rotors. Then modal coupling characteristics evaluation parameter of dual rotor system based on energy distribution relationship is proposed. Using the coupling factor defined, the correlation between the inter-shaft bearing support feature and the modal coupling characteristics is discussed. The results show that, placing the inter-shaft bearing near the mass center of low pressure turbine can effectively restrain the mode coupling, meanwhile the proportion of bearing strain energy can also reflect the mode coupling characteristics of dual rotor system to a certain extent. Then a method of controlling the response coupled vibration of dual rotor system with inter-shaft bearing, based on the principle of mode superposition, is proposed. An example verifies the method can control the response coupling vibration of dual rotor system in wide speed range and under complex excitation conditions.

Vibrio parahaemolyticus (V. parahaemolyticus) is a common pathogen in seafood. The use of antibiotics is a primary tool to prevent and control V. parahaemolyticus in the aquaculture industry. However, V. parahaemolyticus combats the damage caused by antibiotics by forming biofilms under certain conditions. In this study, we analyzed the antibacterial effect and the characteristics of V. parahaemolyticus by experimentally determining the minimum inhibitory concentration (MIC) and the fractional inhibitory concentration index (FICI) values of a combination of the Litsea cubeba essential oil (LCEO) and several commonly used V. parahaemolyticus antibiotics. The bactericidal effect of the essential oil alone and essential oil in combination with the antibiotics were evaluated with time-kill curves. The damage to cell membranes and cell walls were assessed by measuring the content of macromolecules and alkaline phosphatase (AKP) released into the supernatant using V. parahaemolyticus ATCC17802 as the experimental strain. The membrane structure was observed by transmission electron microscopy. The results showed that the MIC value of the LCEO was 1,024 μg/mL, and the LCEO FICI values in combination with tetracycline or oxytetracycline hydrochloride was 0.3125 and 0.75, respectively, indicating synergistic and additive effects. Moreover, LCEO inhibited the growth and promoted the removal of biofilms by reducing the content of hydrophobic and extracellular polysaccharides on the cell surface. This study provides a reference for studying the antibacterial activity of LCEO and the combination of antibiotics to prevent and control the formation of biofilms by V. parahaemolyticus.

We undertook U-Pb-Hf isotope testing of detrital zircons from Late Paleozoic sedimentary rocks in the Jilin Province, NE China, with the aim of constraining the tectonic evolution of eastern Central Asian Orogenic Belt. The age populations of the detrital zircons from the sandstone of the Jiefangcun Formation in the Songliao Block are ~2234, ~1782, ~1030–921, ~817, ~540, and ~381–254 Ma, whereas those of the zircons from the greywacke of the Permian Kedao Formation in the Songliao Block yield are ~2436, ~1905, ~1692, 1146–1170, ~554–498, and ~342–255 Ma. Combined Hf isotope characteristics, these ages reveal that: (1) rocks from the Jiefangcun and Kedao formations were deposited after 254 and 255 Ma, respectively; (2) these formations were sourced mainly from the Songliao Block and the Jiamus Terrane in the eastern CAOB and to a lesser amount, from the northern margin of the NCC; and (3) it appears that several remnants of ancient Precambrian basement occur adjacent to these Late Paleozoic strata that occur within the microcontinental blocks. Detrital zircons from the silty sandstone of the Miaoling Formation in the western margin of the Khanka Terrane yield peak age populations of 508–476, 463–396, and 348–258 Ma, having similar eHf(t) values to those obtained from zircons within the Jiamusi Terrane. These data indicate that (1) deposition of the Miaoling Formation in the western margin of the Khanka Terrane had started by 258 Ma, and (2) these sediments were sourced mainly from the Jiamusi Terrane and local magmatic rocks. The widespread occurrence of detrital zircons with ages of 480–550 Ma and positive eHf(t) values within the Late Paleozoic strata in the Songliao Block and the Jiamusi–Khanka Terrane, indicates that the amalgamation of these blocks took place during the middle stage of the Paleozoic, probably after the Silurian, prior to the Late Permian.

Characterizing atom/ion mobility in superionic materials is one of the most essential topics. In this work, we show that the copper ion mobility in a promising thermoelectric material Cu x AgSe y (x, y = 0.98, 1.02), can be significantly changed by modulating the element ratio, x/y. With 63 Cu NMR linewidth as a direct measure of the copper ion mobility, we observed distinguishable Cu ion mobility in the samples with different ratios even under ambient temperatures. This distinction was further evaluated in terms of correlation times and activation energy of copper diffusion. The contrast in ion mobility could be understood from the point of view of vacancy mediation. This work gives fruitful information for understanding ion dynamics and related topics.

Room-temperature ionic liquids based on the bis ((trifluoromethyl)sulfonyl)-imide anion with the tributyl phosphate (TBP) system employed to extract lithium ion from salt lake brine with a high Mg/Li ratio. The influences of cation structure, concentration of ionic liquid and phase ratio on extraction efficiency were investigated. Results indicated that N-butyl pyridinium bis((trifluoromethyl)sulfonyl)imide (BD) has high extraction efficiency for lithium; tributylmethylammomium bis((trifluoromethyl)sulfonyl)imide (JA) has lower extraction efficiency for lithium and impurity ions but exhibits better selectivity; when cation exchange mechanism occurs during solvent extraction by using ionic liquids as a synergistic extraction agent, the cation more hydrophobic was, the more difficult for it to enter the solution exchange process.

A green and efficient liquid–liquid extraction system was developed for the separation of lithium isotopes by using hydrophobic ionic liquids (ILs = [C4,6,8,10mim]+[NTf2]−) as extraction organic phase and benzo-15-crown-5 (B15C5) as complexing agent. The maximum single-stage separation factor α of 6Li/7Li obtained in this study was 1.029 ± 0.001, indicating 6Li was enriched in ionic liquid phase while 7Li was concentrated in the aqueous phase. The lithium ion was extracted into the ionic liquid in the formation of 1:2 complex [Li+(B15C5)2]. The negative data of thermodynamic parameters (∆ H0 and ∆ G0) suggest that the extraction system was a spontaneous exothermic process. In addition, effective lithium isotopes separation factor and the extraction efficiency of lithium ions can be gained in the condition of lower temperature with softer counter anions in the novel extraction system.

A novel phosphonium ionic liquid (IL), tetrabutylphosphonium bis(2,4,4-trimethylpentyl)phosphinate([P 4444 ][BTMPP]), was prepared and characterized by NMR spectroscopy. The solvent extraction behavior of lithium from aqueous solution by this IL in toluene was investigated. The extraction behavior was carried out as a function of various parameters such as aqueous acidity, temperature and extractant concentration. The extraction efficiencies obtained in [P 4444 ][BTMPP] were compared with those observed in molecular extractant bis(2,4,4-trimethylpentyl) phosphinic acid (HBTMPP), from which the anion of the ionic liquid extractant was prepared. The extraction efficiency for extraction of lithium by [P 4444 ][BTMPP] was much higher than that for extraction by HBTMPP. The extracted species were ascertained from slop analysis method which indicated 1:1 (metal:ligand) ratio in the complex. In addition, the effects of thermodynamic parameters, the stripping of lithium from the ionic liquid, and the reusability of the phosphonium ionic liquid were studied in detail.

Extraction of Li+ ions from salt lake brine into an ionic liquid 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([C2mim][NTf2]) mixed with tri-n-butyl was investigated. The extraction mechanism was been studied using UV–Vis spectroscopy From the temperature dependence data, the thermodynamic functions values (ΔG°, ΔH°, and ΔS°) were calculated. Furthermore, stripping of metals from ionic liquid phase to an aqueous phase by hydrochloric acid was accomplished.

Atomic-scale dynamics of a representative noble metal chalcogenide superionic conductor, stromeyerite (CuAgS), were examined by nuclear magnetic resonance (NMR) spectroscopy at various temperatures. Motional narrowing of 63 Cu NMR line width was found in its cubic phase, demonstrating copper ions start diffusing via a hopping process. Moreover, the absence of 63 Cu NMR signal in its orthorhombic or hexagonal phases was discussed, which could be well explained by copper ordering and reduced local symmetry at copper sites. The above NMR results are relevant for understanding its electron-crystal phonon-liquid behaviors and transient structure-transformation, which are associated with extremely low thermal conductivities and abnormal change of thermal power during superionic phase transition in this material.

Two non-fluorinated ionic liquids (ILs), namely tetrabutylammonium bis(2-ethylhexyl)-phosphate, [N4444][DEHP], and tetraoctylammonium bis(2-ethylhexyl)-phosphate, [N8888][DEHP], were synthesized and fully characterized by 1H and 13C NMR spectroscopy. These functionalized ILs were subsequently evaluated in terms of their ability to extract lithium ions from aqueous solution. The extraction efficiencies of these functionalized ILs for lithium ions were measured as a function of various extraction parameters, including aqueous acidity, temperature and extractant concentration. The extracted species were determined using a slope analysis method, which indicated that the ILs formed a 1:1 (metal:ligand) complex. Fourier transform infrared spectroscopy studies were conducted to better understand the nature of the extracted species. We also investigated the stripping of the lithium ions from the organic phase and the re-use of the ionic liquid in a subsequent extraction step.

In this paper, a novel liquid-liquid extraction system was investigated for the selective separation of lithium isotopes using ionic liquid (IL) and dichloroethane as extraction solvent and dibenzo-14-crown-4 (DB14C4) as extractant. Results showed that the separation performance of DB14C4 has been improved after the ILs were involved in the extraction process. The maximum single stage separation factor α for 6Li/7Li obtained in the present study was 1.021. The light lithium isotope 6Li and the heavy lithium isotope 7Li were concentrated in organic phase and solution phase, respectively. The order of the single stage separation factor obtained in different lithium salts was LiI > LiBr > LiClO4 > LiCl. From the temperature dependence data, the thermodynamic functions values of the lithium isotope exchange reaction were calculated.

At present, the amount of data generated by IoT terminal devices has become extremely large. The traditional centralized data processing model centered on the cloud computing model has been unable to support the current power IoT system. This paper proposes an intelligent fault detection system for power IoT devices based on edge computing for the defects of the cloud center computing model. The system model is divided into cloud center layer, edge layer, and field layer. In the field layer, the DTW complement algorithm is used to complement the sensor data; the DNN algorithm is used to implement the fault primary classification in the edge layer, and the classification result is uploaded to the cloud center layer; the correlation between the data is used in the cloud center layer to realize the fault classification. After that, an experiment was designed to verify the efficacy of the modified model.

Target assignment for unmanned aerial vehicle (UAV) swarm has been a research hotspot in academic and industry communities. The current methods mainly focus on multiple targets assignment in planes or few targets assignment in solids. However, they ignore three-dimensional scenarios for UAV swarm and multiple targets characteristics for assignment problem. To solve these issues, we propose a multi-target intelligent assignment model. Firstly, we introduce damage cost and time cost to evaluate the system performance of swarm and time performance in three-dimensional scenarios. Then, we design a bio-inspired swarm intelligence optimization algorithm to find the optimal multiple targets assignment and to balance the two costs and multiple constraints simultaneously. This algorithm regards UAVs as several parallel biological sub-populations, which adopts the multi-layered optimization strategy to select the suitable assignment sequence. The simulation results demonstrate that the proposed method is effective for multi-target assignment in three-dimensional scenarios.

A novel liquid–liquid extraction system was investigated for the selective separation of lithium isotopes using ionic liquids (ILs = [C 6,8,10,12 mim] + [PF 6 ] － ) as extraction solvent and benzo-15-crown-5 (B15C5) as extractant. The effects of the concentration of lithium salt, counter anion of lithium salt, initial pH of aqueous phase, and extraction temperature on the lithium isotopes separation were studied. The maximum single-stage separation factor α of 6 Li/ 7 Li obtained in the present study was 1.038 ± 0.002, indicating the lighter isotope 6 Li was enriched in organic phase while the heavier isotope 7 Li was concentrated in the aqueous phase. The formation of 2:1 complex Li(B15C5) 2 + in the IL phase was determined on the basis of slope analysis method. The large value of the free energy change (− G 0 = 77.87 J mol −1 ) indicated the high separation capability of the lithium isotopes by B15C5/30%CH 3 Cl-70% C 6 mimPF 6 mixture extraction system. Lithium in Li(B15C5) 2 + complex was stripped by 0.5 mol·L −1 HCl solution. The extraction system offers high efficiency, simplicity application prospect to separation lithium isotope separation from LiCl solution.

The use of a transoral atlantoaxial reduction plate (TARP) system is an effective surgical approach for the treatment of basilar invagination. With the aim of improving the therapeutic efficacy of the TARP operation, we conducted a voxel-based morphometric study to quantitatively investigate the descent of the odontoid process and craniocervical volume changes.We enrolled 20 patients with basilar invagination who underwent a TARP procedure. Craniocervical computed tomography (CT) scanning and a 3-dimensional (3-D) reconstruction of the craniocervical junction were performed. Craniocervical volumes and odontoid process descent distances were measured preoperatively and postoperatively. Individual neurological function was evaluated according to the Japanese Orthopaedic Association (JOA) scoring system for cervical disorders. Pearson correlation analysis was applied for statistical testing.Surgical efficacy (the JOA-score improvement rate) was significantly associated with the craniocervical volume improvement rate, the odontoid descent distance, and the absolute craniocervical volume changes (p0.01 for all), with correlation coefficients (r) of 0.83, 0.80, and 0.61, respectively. No significant correlation was noted between surgical efficacy and age, symptom duration, preoperative neurological function, odontoid process displacement, or change in clivus-odontoid angle (p0.05). The craniocervical volume improvement rate was significantly associated with the odontoid descent distance (r = 0.8; p0.01), but it was not associated with the odontoid displacement or the change in the clivus-odontoid angle (p0.05).We found that the odontoid descent distance predicted the craniocervical volume improvement rate following TARP procedures in patients with basilar invagination, and we believe that both can serve as predictors of surgical efficacy. We believe that planning the odontoid descent distance preoperatively may help to improve the efficacy of TARP operations.Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

The key progress in the development of solar cells based on mixed organic-inorganic halide perovskite was reviewed. Perovskite solar cells (PSCs) have developed rapidly and achieved highest efficiency exceeding 20% in these years. The origin, working principle and fabrication technology of PSCs are stated, and several promising methods to realize the industrialization of the solar cell modules have been put forward. Meanwhile, two main problems existing in PSCs have been pointed out, hysteresis in the photocurrent density-voltage measurement and the instability of perovskite, which have impacted the application of PSCs seriously. Efforts and study in order to solve these problems are also listed. The fundamental mechanism still needs further investigation so as to improve the performance of PSCs and realize their large-scale application eventually.