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Context: The quasi-metallic properties of stanene limit its prospects in optoelectronic devices. Based on first-principles calculations, a systematic study is conducted on the tuning effects of surface hydrogenation and Al atom doping on the electronic and optical properties of stanene. Surface hydrogenation serves as an ideal way to open the forbidden band of stanene, and Al atom doping further increases hydrogenated stanene (stanane) band gap to 0.460 eV. Deformation has a minor impact on the stability of the stanane-Al structure, while shear strain can effectively modulate the band gap engineering of the doped system, reducing the band gap value from 0.460 to 0.170 eV. Deformation induces a redshift in the absorption peak and reflectance, also slowing down the rate of decrease in the absorption coefficient, and enhancing the peak value of light reflectance, which is positively correlated with the degree of shear strain. These findings hold promise for expanding the potential application of monolayer stanane in semiconductor devices. Methods: All calculations are performed using CASTEP module in Materials Studio based on the density functional theory (DFT). The Perdew–Burke–Ernzerhof (PBE) generalized gradient approximation (GGA) is employed to describe the exchange–correlation energy (Perdew et al., Phys Rev Lett 77(18), 1996). We construct models for both stanene and stanane. The original unit cell of stanene has two Sn atoms, while stanane consists of two Sn atoms and two H atoms, and expand them to a 3 × 3 × 1 supercell with a vacuum layer of 20 Å in height to prevent interlayer coupling. After convergence testing, the plane-wave cutoff energy is set to 450 eV, and the energy convergence threshold is set to 1 × 10−5 eV. The maximum residual stress for each atom is set to 0.01 eV/Å. Brillouin zone sampling is performed using a 6 × 6 × 1 k-point mesh based on the Monkhorst–Pack method (Monkhorst and Pack, Phys Rev B 13(12), 1976). The k-point accuracy of the density of states and optical properties is 9 × 9 × 1. All calculations are performed using the more advanced OTFG ultrasoft pseudopotential, and structural relaxations are performed using supercells to ensure that the model is fully relaxed. We use the HSE06 functional to calculate the energy band structures of stanane-Al deformed to 0%, 4%, and 8%, resulting in band gap values of 1.465 eV, 1.368 eV, and 1.016 eV, respectively. These values are significantly higher than those obtained using the PBE functional (0.460 eV, 0.397 eV, and 0.170 eV). However, the shapes and trends of the band structures obtained from both PBE and HSE06 calculations are similar. Additionally, the calculation time needed by HSE06 is greatly longer than PBE, which exceeds the capabilities of our computer hardware, and cannot support all subsequent calculations. To investigate the influence of deformations on the variation of band gap values and to conserve computational resources, the subsequent calculations in this study use the PBE functional. [ABSTRACT FROM AUTHOR]

Background: This study aimed to evaluate the safety and efficacy of robot-assisted percutaneous pars–pedicle screw fixation surgery for treating Hangman's fracture. Methods: The study involved 33 patients with Hangman's fracture who underwent robot-assisted fixation surgery using cannulated pars–pedicle screws through a percutaneous approach. The primary parameter evaluated was the accuracy of the screws according to the Gertzbein–Robbins scale, using postoperative CT images. Secondary parameters included the duration of surgery, intraoperative blood loss, postoperative hospital stay, and neurovascular injury. Results: A total of 60 pars–pedicle screws were placed in 33 patients. Based on the Levine and Edwards classification, the patients included 12 cases of type I, 15 cases of type II, five cases of type IIa, and one atypical case. The average operative time was 92.4 ± 37.4 min, and the average blood loss was 22.4 ± 17.9 ml. Fifty-five of 60 screws were successfully placed within the bone. No screw-related neurovascular injury was observed, and satisfactory reduction was achieved in all cases. Conclusion: Robot-assisted percutaneous pars–pedicle screw fixation is a safe and feasible method for treating Hangman's fracture. Trial registration: The study was retrospectively registered and approved by our center's institutional review board. [ABSTRACT FROM AUTHOR]

Water-based lubricants with different fractions of TiO2 nanoparticles ranging from 1.0 to 9.0 wt.% were utilized to study the lubrication mechanisms during micro rolling tests and the tribological behaviour of nanolubricants during the micro rolling of copper foils. The results indicate that the application of TiO2 nanolubricants remarkably improves the surface quality of rolled copper foils during rolling processes. For lubricants with inadequate TiO2 nanoparticles, it is found that few TiO2 nanoparticles enter the contact regions between the rolls and foils, causing insufficient lubrication during rolling processes. Instead, for lubricants with excessive TiO2 nanoparticles, obvious agglomeration occurs at the contact regions and promotes the generation of voids on the surface of the rolled foils, thereby deteriorating the surface quality of the rolled copper foils. In addition, it is found that the surface quality of rolled foils is improved by utilizing a large reduction ratio. Overall, the fraction of 3.0 wt.% TiO2 nanolubricants is optimal to improve the lubrication conditions at the contact regions, thereby improving the surface quality of the rolled copper foils. [ABSTRACT FROM AUTHOR]

Improving energy storage density and efficiency is the ultimate goal of dielectric materials used in ceramic capacitors. Among different dielectric materials, dielectrics in thin film state own superior energy performances due to less defects compared with ceramic. Herein, we report an optimized lead-free Zr-modified BiMg 0.5 Zr 0.04 Ti x-0.04 O 3 composition with enhanced energy storage behavior via microstructural engineering. Rapid annealing can result in poorly crystallization in the film matrix confirmed by grazing incident X-ray diffraction GIXRD. The excess Ti source can effectively increase polarization and dielectric breakdown till to 97.0 μ C/cm2 and 3403 kV/cm at x = 0.775, respectively. The optimized energy properties can be achieved at x = 0.775 with a high recoverable energy storage density W reco of 87.8 J/cm3 and an efficiency η of 50%, indicative of excellent stability of storing electricity for the applications of pulse power electronics. [ABSTRACT FROM AUTHOR]

The effect of varying hot rolling finishing temperature and the application of intermediate annealing on the microstructure, texture evolution, and mechanical properties—including forming, hemming, and roping properties—of Al-Mg-Si alloy sheets was systematically investigated. The hot-rolled plate with a higher rolling finishing temperature exhibits a significantly higher volume fraction of Cube texture which is readily retained and inherited to the final state microstructure. A substantial quantity of Mg 2 Si particles can also be observed in this plate, while the amount notably decreases at lower rolling finishing temperatures. These large quantities of Mg 2 Si hinder the PSN effect, subsequently encouraging Cube texture and hindering Cube ND texture formation during solute solution. Following intermediate annealing, Ostwald ripening mechanism leads to finer Mg 2 Si particles dissolve while the coarser Mg 2 Si continue to grow, reducing the obstruction to the PSN effect. The T4P sheets without intermediate annealing exhibit a significant volume fraction of Goss texture. Goss texture can be effectively minimized by applying intermediate annealing process and thus almost disappears in T4P sheets that undergo intermediate annealing. Cube texture proved advantageous for hemming processes but detrimental to both formability and roping performance; thus, it should be modulated within an optimal range. On the other hand, Goss texture negatively impacted all mechanical properties and should be minimized or eliminated. Optimal comprehensive properties can be achieved by lowering the hot rolling finishing temperature and implementing a suitable intermediate annealing treatment. • Mg 2 Si inhibits the PSN effect. • The Goss texture diminishes by inter-annealing. • Roping is caused by texture bands aligning the RD. • Decreasing the hot-rolled finishing temperature and adopting inter-annealing achieve best comprehensive properties. [ABSTRACT FROM AUTHOR]

Diosmin is a flavone glycoside with a confirmed therapeutic effectiveness on the chronic venous disorders. In this paper, the classical mouse depression model induced by LPS was established to explore the effect of Diosmin on depression. Firstly, we found that Diosmin could inhibit the inflammation and neuronal damage in the prefrontal cortex (PFC) of mice, and thus alleviating the LPS-induced depressive-like behaviors. Specifically, Diosmin treatment significantly suppressed the secretion of pro-inflammatory cytokines (TNF-α, IL-6 and IL-1β), reduced the activation of microglia, and inhibited the expression of NLRP3 inflammasome and its downstream effector caspase-1 in both PFC of mice and BV2 microglial cells exposed to LPS. Then, we demonstrated that pretreatment with Diosmin dramatically suppressed the LPS-induced oxidative stress in the PFC of mice, manifested in the decrease of reactive oxygen species and malondialdehyde while increase of catalase activity. Consistently, Diosmin also alleviated the oxidative stress in BV2 cells exposed to LPS. Finally, we confirmed that Diosmin effectively suppressed the activation of NF-κB signaling pathway in the PFC of LPS-treated mice. Further in vitro experiments also verified that Diosmin could prevent the p65 transposition to nucleus in LPS-treated BV2 cells, suggesting that the antidepressant effects of Diosmin are partially mediated by blocking of NF-κB signaling. Taken together, this study proposes the potential antidepressant effect of Diosmin, which provides useful support to the development of new therapies for depression. • Diosmin inhibits the inflammation and neuronal damage in the prefrontal cortex. • Diosmin restores the oxidative homeostasis in the prefrontal cortex. • Diosmin inhibits the microglia-mediated inflammation both in vivo and in vitro. • Diosmin ameliorates the depression progression via blocking of NF-κB pathway. [ABSTRACT FROM AUTHOR]

Energy metabolic processes play important roles for tumor malignancy, indicating that related protein-coding genes and regulatory upstream genes (such as long noncoding RNAs (lncRNAs)) may represent potential biomarkers for prognostic prediction. This study will develop a new energy metabolism-related lncRNA-mRNA prognostic signature for lower-grade glioma (LGG) patients. A GSE4290 dataset obtained from Gene Expression Omnibus was used for screening the differentially expressed genes (DEGs) and lncRNAs (DELs). The Cancer Genome Atlas (TCGA) dataset was used as the prognosis training set, while the Chinese Glioma Genome Atlas (CGGA) was for the validation set. Energy metabolism-related genes were collected from the Molecular Signatures Database (MsigDB), and a coexpression network was established between energy metabolism-related DEGs and DELs to identify energy metabolism-related DELs. Least absolute shrinkage and selection operator (LASSO) analysis was performed to filter the prognostic signature which underwent survival analysis and nomogram construction. A total of 1613 DEGs and 37 DELs were identified between LGG and normal brain tissues. One hundred and ten DEGs were overlapped with energy metabolism-related genes. Twenty-seven DELs could coexpress with 67 metabolism-related DEGs. LASSO regression analysis showed that 9 genes in the coexpression network were the optimal signature and used to construct the risk score. Kaplan-Meier curve analysis showed that patients with a high risk score had significantly worse OS than those with a low risk score (TCGA: HR = 3.192 , 95 % CI = 2.182 ‐ 4.670 ; CGGA: HR = 1.922 , 95 % CI = 1.431 ‐ 2.583). The predictive accuracy of the risk score was also high according to the AUC of the ROC curve (TCGA: 0.827; CGGA: 0.806). Multivariate Cox regression analyses revealed age, IDH1 mutation, and risk score as independent prognostic factors, and thus, a prognostic nomogram was established based on these three variables. The excellent prognostic performance of the nomogram was confirmed by calibration and discrimination analyses. In conclusion, our findings provided a new biomarker for the stratification of LGG patients with poor prognosis. [ABSTRACT FROM AUTHOR]

Glioblastoma (GBM) is a most aggressive primary cancer in brain with poor prognosis. This study aimed to identify novel tumor biomarkers with independent prognostic values in GBMs. The DNA methylation profiles were downloaded from The Cancer Genome Atlas and Gene Expression Omnibus database. Differential methylated genes (DMGs) were screened from recurrent GBM samples using limma package in R software. Functional enrichment analysis was performed to identify major biological processes and signaling pathways. Furthermore, critical DMGs associated with the prognosis of GBM were screened according to univariate and multivariate cox regression analysis. A risk score-based prognostic model was constructed for these DMGs and prediction ability of this model was validated in training and validation data set. In total, 495 DMGs were identified between recurrent samples and disease-free samples, including 356 significantly hypermethylated and 139 hypomethylated genes. Functional and pathway items for these DMGs were mainly related to sensory organ development, neuroactive ligand–receptor interaction, pathways in cancer, etc. Five genes with abnormal methylation level were significantly correlated with prognosis according to survival analysis, such as ALX1, KANK1, NUDT12, SNED1, and SVOP. Finally, the risk model provided an effective ability for prognosis prediction both in training and validation data set. We constructed a novel prognostic model for survival prediction of GBMs. In addition, we identified five DMGs as critical prognostic biomarkers in GBM progression. [ABSTRACT FROM AUTHOR]

A systematic study was carried out to evaluate the effects of cold rolling and annealing processes on the ridging severity of ferritic stainless steel (FSS). Both microstructural refinement and texture optimisation were achieved with an optimised processing schedule to improve the ridging resistance of FSS. Coarse grain bands comprising of primarily {112} <110> oriented grains were found to form inside cold-rolled and annealed FSS sheets. The effects of annealing schedules and the resultant microstructure and texture on the ridging behaviour of FSS are discussed. The results indicate that the reduction in the fraction of {001} <110> orientation by optimisation of the rolling processes contributes to reduce the ridging height of the FSS during the subsequent forming process. Through extending soaking time and under 880 °C during final annealing step, a maximum of 30% reduction in ridging height can be achieved with a refined microstructure and texture of FSS, improving the surface quality of FSS during subsequent forming processes. [ABSTRACT FROM AUTHOR]

Background. This study aims to develop novel signatures for glioblastoma multiforme (GBM). Methods. GBM expression profiles from The Cancer Genome Atlas (TCGA) were downloaded and DEGs between tumor and normal samples were identified by differential expression analysis (DEA). A risk signature was developed by applying weighted gene coexpression network analysis (WGCNA) and Cox regression analysis. Patients were divided into high and low risk group, followed by evaluating the performance of the signature via Kaplan-Meier curve analysis. In addition, the prognostic significance of the signature was further validated using an independent validation dataset from Chinese Glioma Genome Atlas (CGGA). DEGs between high and low risk group were subjected to functional annotation. Results. A total of 748 DEGs were identified between primary tumor and normal samples. Following WGCNA and Cox regression analysis, 6 DEGs were identified and used to construct a risk signature. The signature showed high performance in both training and validation dataset. Subsequently, 397 DEGs were identified between high and low risk group. These DEGs were mainly enriched in terms related to calcium signaling, cAMP-mediated signaling, and synaptic transmission. Conclusions. The risk signature may contribute to GBM diagnosis in future clinical practice. [ABSTRACT FROM AUTHOR]

Cermet and steel material bonding is a challenging task, due to their large difference of physical properties, e.g. coefficient of thermal expansion. In this study, a hot compaction diffusion bonding method was employed to fabricate a small-dimensional bimetallic composite of WC-10Co and high strength AISI 4340 steel, where the cermet was used in powder form and the steel as solid. The bimetal composite was characterised by microstructural analysis and mechanical properties evaluation. The interface microstructure reveals a successful metallurgical bonding between the cermet and steel materials. The influence of sintering temperature (1050–1250 °C) was examined at intervals of 50 °C. This study shows that the properties of sintered powder and the bonding quality with the steel improve with an increase in sintering temperature. A bonding beneficiary reaction layer was observed to grow at the joining interface by mutual diffusion of the alloying elements, which increases with the increasing temperature. The maximum width of the reaction layer observed was 4.13 μm and consists mainly of intermetallic ternary carbides. The bonding shear strength of the interface is found to be slightly higher than claimed in previous studies. The developed bimetal composite could be used in applications where a combination of high strength and hardness is required. [ABSTRACT FROM AUTHOR]

Bimetal composites have wide applications due to their excellent overall performance and relatively low cost. In this study, the formability of stainless/carbon steel bimetal medium-thick composite in the stamping process without blank holder was investigated by finite element (FE) simulations and experiments. Uniaxial tensile tests on substrate metal (carbon steel) and clad metal (stainless steel) were first conducted, respectively, in order to obtain the material properties of each metal layer required in the FE simulation. Processing variables, including the layer stacking sequence, relative thickness ratios of two layers and friction conditions, were considered, and their effects on the magnitude of press load and distributions of thickness strain for predicting the high-risk region of necking during stamping were discussed. Experimental tests were carried out to verify the simulation results. It is indicated that simulation results can be used as an evaluation indicator to ensure the bimetal medium-thick composite can be safely formed. [ABSTRACT FROM AUTHOR]

In this paper, oil-in-water (O/W) based nanolubricants containing TiO 2 nanoparticles were developed to reduce the rolling force and improve the surface quality of rolled 304 stainless steel product. Practical hot rolling tests with and without application of lubricant were conducted to systematically investigate the effects of the developed O/W based nanolubricants on the rolling force, surface roughness, oxide scale thickness and tribological behaviour. The obtained results indicate that the nanoparticles can enter the deform zone with oil droplets to take a lubrication effect. The optimal lubrication effect can be achieved when the O/W (1% oil mass fraction) based nanolubricant with a TiO 2 mass fraction of 1.5% was applied. The microstructure of oxide scales formed on the hot rolled sample was not significantly affected by TiO 2 nanoparticles in the O/W based lubricant, but the oxide scale growth could be induced by TiO 2 nanoparticles. A discontinuous thin SiO 2 layer at the substrate-scale interface was observed. It can effectively reduce the formation of iron-rich oxides. The novel nanolubricant has a great potential to be applied in the hot steel rolling, to realise the cost-effective and environmental-friendly manufacturing process. [ABSTRACT FROM AUTHOR]

Highlights • A developed analytical model of bending characteristics for bimetal composite was presented. • The movement behaviour of bonding interface relative to neutral and unelongated planes was studied. • Analytical, FE and experimental investigations were conducted on the bending behaviours of bimetal composite. Abstract Analytical, numerical and experimental investigations were conducted on the bending characteristics of duplex stainless steel (2205) and low carbon steel (AH36) bimetal composite in this study, with the aim of providing a reference for the bending and forming processing optimisation of laminated metal composite. An analytical model was developed to predict the deformation behaviour of each segment and particular planes, such as neutral plane, unelongated plane and bonding interface, across thickness section under the plane strain condition during the bending process. The movement track of segments presents that it is better for the bonding interface to avoid experiencing the reverse loaded zone (RLZ) in forming fabrications for less potential defects, and the neutral plane is discontinuous while coinciding with the bonding interface. The thickness change and bending moment of bimetal plate were calculated as a function of the increasing bending curvature by the proposed theoretical model under four conditions classified by different thickness ratios and relative positions of component steel layers. The predicted results show that the relative position affects the thickness change of bent composite plate, but the thickness ratio has a more significant effect on the magnitude of bending moment, as confirmed by finite element (FE) simulation and bending experiments. Graphical abstract Image, graphical abstract [ABSTRACT FROM AUTHOR]

Bonding between tungsten carbide and steel is a challenging task due to their large difference of physical properties. Previous reports were based on solid state bonding. In this study, a powder-solid mechanism was employed for analysing the sintering and bonding process of ultrafine WC (with 8% Co added as binder) powder and solid stainless steel (SS 304). A novel manufacturing mechanism of hot compaction diffusion bonding (HCDB) was implemented to facilitate the bonding process. The influence of temperature varying from 1160 to 1220 °C was investigated with an interval of 20 °C. The experiment is conducted in a vacuum environment at constant pressure of 160 MPa. Under simultaneous effects of temperature and pressure, WC powder was solidified and a diffusion bonding was realised with SS 304. The bonding interface is characterised by three distinctive features, namely properly bonded area, crack appearance and formation of diffusion layer. Generation of micro cracks are examined in the form of single long micro crack, cluster of micro cracks and crack in WC region. An average hardness of 1971 HV was found at 1220 °C, and the maximum mechanical bonding shear strength achieved was 172 MPa. The microstructure morphology, composition distribution, bonding characteristics and crack formation, diffusion mechanism and mechanical properties of the composite bimetal were examined. The fabricated composite bimetal has the potentials in the applications where high hardness and high strength are required simultaneously. [ABSTRACT FROM AUTHOR]

To meet the increasing demand of multifunctional applications of microcomponents, metal composites have been gradually noted in micromanufacturing. In this paper, the formability of aluminium (Al)-copper (Cu) composite foils in micro deep drawing (MDD) was studied, and the mechanism involved was discussed. A two-layered Al-Cu composite with the thickness of 235 µm was selected and first rolled to 50 µm, and then annealed at 200, 300, 400 and 500 °C for 5 min prior to the MDD experiments. The results show that Al-Cu composite foil possesses the best combination of strength and ductility after annealing at 400 °C. With the increase in annealing temperature, the grains of both Al and Cu layers are refined, and in the meantime, the thickness of intermetallic layer also increases. The results from MDD tests indicate that the existence of intermetallic layer has a greater influence on the formability of the composite foil compared to the finer distribution of grains. On the basis of the obtained results, the optimised heat treatment method with the annealing temperature of 300 °C for 1 h was proposed, which was then proved to significantly improve the performance of the Al-Cu composite foil in MDD. [Display omitted] [ABSTRACT FROM AUTHOR]

Highlights: [•] It is difficult for hydrogen to permeate in the W-containing microalloyed steels. [•] W addition induces increased activation energy of hydrogen desorption. [•] Hydrogen charging benefits the ductile to quasi-cleavage fracture transition. [•] Hydrogen embrittlement is caused by the decohesion and internal pressure. [Copyright &y& Elsevier]

Characteristics of hydroclimatic change in the upper reaches of the Minjiang River are analysed using data collected over the past 50 years. The effect of autocorrelation of time series on trend analysis is removed by adopting a pre-whitening technique. Long-term hydrometeorological trend and abrupt changes are analysed by the Mann-Kendall test. The results were validated by the linear trend and Spearman methods. Correlations between runoff change with air temperature and with precipitation were studied with the Pearson method. The results clearly show that average air temperature in the upper reaches of the river is increasing, and precipitation decreasing, with differences in spatio-temporal distribution. Runoff change has a clear positive correlation with precipitation. Meteorological change, especially in precipitation, is the key governing influence of runoff volume. The annual runoff decrease, especially the decrease of inflow in spring and autumn and earlier appearance and longer duration of the low-flow season, will impact greatly on irrigation and municipal water supply. Therefore, relevant measures and further study are necessary. EditorZ.W. Kundzewicz;Associate editorQ. Zhang CitationHuang, X.R., Zhao, J.W., Li, W.H., and Jiang, H.X., 2013. Impact of climatic change on streamflow in the upper reaches of the Minjiang River, China.Hydrological Sciences Journal, 59 (1), 154–164. [ABSTRACT FROM AUTHOR]

Highlights: [•] Hydrogen can be retained in the alloy in air when deformed at 1100°C. [•] Hydrogen addition has a positive effect on the increment of flow stress. [•] The strain rate sensitivity shows an increasing trend with hydrogen. [•] Hydrogen significantly affects the variables introduced in the constitutive models. [Copyright &y& Elsevier]

Investigating fatigue crack growth behavior of materials is crucial to the life design and safety evaluation of engineering structures. During the practical service condition, the temperature keeps changing, which cannot be studied by the traditional fatigue crack growth test method at constant temperature. In this study, we focus on constructing a new thermomechanical fatigue (TMF) crack propagation testing method, developing a thermal deformation compensation method, and proposing an equivalent compliance method suitable for variable temperature conditions based on ASTM E647 standard to measure the crack length. Furthermore, the load‐ and strain‐controlled TMF tests under different phase angles are carried out to prove the validity of the new method. Highlights: A temperature compensation method for the variable temperature test is proposed.A modified compliance method for crack length measurement is developed.The thermomechanical fatigue (TMF) crack propagation testing method was standardized.Only the stress intensity factor range ΔK cannot be used to characterize the fatigue crack growth rate. [ABSTRACT FROM AUTHOR]

Context: In this paper, the optimum coverage of 4.44% and the optimum adsorption sites were determined for the Be3N2 adsorption system of O atoms at different coverages based on density functional theory. The electronic and optical properties of the model were investigated by applying bending deformation to the model at these coverage and adsorption sites. Adsorption of O atoms disrupts the geometrical symmetry of Be3N2, resulting in orbital rehybridization and lowering its band gap. Bending deformation causes the band gap of the adsorbed O atom structure of Be3N2 to first increase and then decrease, resulting in the modulation of its band gap. With increasing bending deformation, the adsorbed system is redshifts, and the degree of redshift increases with increasing bending deformation. Methods: All calculations in this paper were performed using the first-principles-based CASTEP module of Materials Studio (MS). The generalized gradient approximation (GGA) plane-wave pseudopotential method and the Perdew-Burke-Ernzerhof (PBE) Perdew et al. Phys Rev Lett 77:3865, 1996 generalized functional were used in the geometry optimization and calculation process to calculate the exchange–correlation potential between electrons. The effect of coverage on the electronic and optical properties of the Be3N2-adsorbed O atom system was investigated by adsorbing different numbers of O atoms on a monolayer of Be3N2. The Be3N2 protocell contains two N atoms and three Be atoms with a space community of P6/MMM (No.191). The original cell was expanded 3 times along the direction of the base vectors a and b in the Be3N2 plane to create a 3 × 3 × 1 monolayer Be3N2 supercell system. A vacuum layer of 15 Å is set in the direction of the crystal plane of the vertical monolayer Be3N2 supercell to eliminate interactions between adjacent layers. In the overall energy convergence test of the Be3N2 supercell, the plane wave truncation energy was set to 500 eV, and the energy difference between the calculations given in the literature Reyes-Serrato et al. J Phys Chem Solids 59:743-6, 1998 using 550 eV was less than 0.01 eV, verifying the reliability of the data at a truncation energy of 500 eV. The Monkhorst–Pack special k-point sampling method Monkhorst et al. Phys Rev B 13:5188, 1976 was used in the structural calculations, and the grid was set to 3 × 3 × 1. The geometric optimization parameters are set as follows: the self-consistent field iteration convergence criterion is 2.0 × 10−6 eV, and the iterative accuracy convergence value is not less than 1.0 × 10−5 eV/atom for the total force of each atom and less than 0.03 eV/Å for all atomic forces. In addition the high-symmetry k-point path is taken as Γ(0,0,0) → M(0,0.5,0) → K(− 1/3,2/3,0) → Γ(0,0,0) Chen et al, AIP Adv 8:105105, 2018. [ABSTRACT FROM AUTHOR]

The hot deformation behaviour and interfacial microstructure evolution have a critical influence on the hot workability and mechanical properties of bimetal composite. This study investigated the flow performance and interfacial characteristics of 2205 duplex stainless steel/AH36 low carbon steel bimetal composite (2205/AH36 BC) at elevated temperatures, based on the hot tensile tests over the temperature range of 950–1250 °C and strain rate range of 0.01–1 s−1. The results indicate that the deformation behaviour of 2205/AH36 BC is similar to that of AH36 low carbon steel at high temperatures, and the softening mechanism of bimetal composite significantly depends on the imposed working temperatures and strain rates, which has been verified by the electron backscatter diffraction (EBSD) observation of microstructure evolution. Extra geometrically necessary dislocations (GNDs) were observed to accumulate in AH36 carbon steel layer adjacent to the interface after the hot working test at relatively low strain rates, resulting from the different thermal expansions and hot ductility between the 2205 stainless steel and AH36 carbon steel, and some existing defects on the interface from the previous hot rolling process. These observations can be employed as a reference to make the medium-thick bimetal composite be fabricated to the final products with hot working process in practice. • The deformation behaviours of 2205/AH36 bimetal composite are controlled by DRX at high temperatures or low strain rates. • The GND density of 2205 steel and AH36 steel layers reduces after the hot tensile test at the relatively low strain rates. • The interfacial GND density and nano hardness value of 2205/AH36 bimetal composite show a peak after hot tensile tests. [ABSTRACT FROM AUTHOR]

Product miniaturization is a trend for facilitating product usage, enabling product functions to be implemented in microscale geometries, and aimed at reducing product weight, volume, cost and pollution. Driven by ongoing miniaturization in diverse areas including medical devices, precision equipment, communication devices, micro-electromechanical systems (MEMS) and microsystems technology (MST), the demands for micro metallic products have increased tremendously. Such a trend requires development of advanced micromanufacturing technology of metallic materials for producing high-quality micro metallic products that possess excellent dimensional tolerances, required mechanical properties and improved surface quality. Micromanufacturing differs from conventional manufacturing technology in terms of materials, processes, tools, and machines and equipment, due to the miniaturization nature of the whole micromanufacturing system, which challenges the rapid development of micromanufacturing technology. Against such a background, the Special Issue "Micromanufacturing of Metallic Materials" was proposed to present the recent developments of micromanufacturing technologies of metallic materials. The papers collected in the Special Issue include research articles, literature review and technical notes, which have been highlighted in this editorial. [ABSTRACT FROM AUTHOR]

• The unique hot flow behaviour of bimetal composite different from that of a single material was analysed. • A physically-based constitutive model considering DRV and DRX softening mechanisms for bimetal composite was established. • A mixture law of bimetal composite considering the strain and stress partitioning was developed. • Analytical, FE and experimental investigations were conducted on the flow behaviour of bimetal composite. The flow behaviour and strain partitioning of 2205 duplex ferritic-austenitic stainless steel/AH36 low carbon steel bimetal composite (2205/AH36 BC) were investigated at elevated temperatures in this study. A physically-based constitutive model was established to describe the flow behaviour of bimetal composite based on the stress–strain relationships obtained from hot tensile tests, which were performed on a Gleeble 3500 thermal-mechanical test simulator over the temperature range of 950–1250 °C and strain rate range of 0.01–1 s−1. The stress and strain partitioning of bimetal composite was analysed to develop a mixture law of flow stress under those hot working conditions, due to the different strain contributions of each material on the total flow behaviour of bimetal composite. The developed constitutive model and the mixture law considering strain partitioning were both adopted to predict the stress–strain curves and used in finite element (FE) simulation model to calculate the peak loads of 2205/AH36 BC at 1000 °C. It is found that the softening mechanisms of 2205/AH36 BC changes depending on the externally imposed working temperatures and strain rates. The contribution of AH36 carbon steel layer on total stress is relatively more than that of 2205 stainless steel layer at high temperatures, as a result of the occurrence of stress partitioning. The proposed constitutive model, instead of the mixture law, is recommended to be used in the FE simulation of practical hot working of bimetal composite due to its high accuracy. [ABSTRACT FROM AUTHOR]

Context: The incorporation of functionalized carbon nanotubes can enhance the mechanical properties of cement-based materials. However, the types of functional groups and their roles in composite materials are not yet clear. In this study, molecular dynamics (MD) simulation methods were employed to investigate the mechanical performance of hybridized calcium silicate hydrate gel reinforced with pure carbon nanotubes, epoxy-coated carbon nanotubes, carboxylated carbon nanotubes, and hydroxylated carbon nanotubes. The results indicate that the addition of all four types of nanotubes can enhance the mechanical properties of hydrated calcium silicate gel compared to pure C–S–H. Tensile loading results show that carbon nanotubes can act as bridges for microcracks in the composite material, and functionalized nanotubes exhibit a better reinforcing effect than pure carbon nanotubes. Under tensile stress, hydroxylated nanotubes are more effective in increasing the toughness of the composite material, while carboxylated nanotubes tend to enhance the strength of the composite material. The compressive loading results indicate that the compressive strength of cement-based materials is higher than their tensile strength. Overall, carboxylated nanotubes show particularly remarkable performance in enhancing the mechanical properties of cement-based materials. Compared to pure C–S–H gel, the tensile and compressive elastic moduli of carboxylated nanotube/C–S–H composite material increased by 18.13% and 34.78%, respectively. Its tensile and compressive strengths also increased by 30.40% and 40.23%, respectively. Method: All molecular dynamics simulations were performed on the classical computational simulation platform LAMMPS. In this paper, the parameters in the ClayFF force field are chosen to simulate calcium hydrated silicate (/C–S–H), and the ClayFF-CVFF combined force field is used to simulate the mechanical properties of the CNT/C–S–H molecular model structure. [ABSTRACT FROM AUTHOR]

Background: Parkinson's disease (PD) is a neurodegenerative disorder characterized by the loss of dopaminergic (DA) neurons in the substantia nigra (SN). Microglia-mediated neuroinflammation has been largely considered one of main factors to the PD pathology. MicroRNA-218-5p (miR-218-5p) is a microRNA that plays a role in neurodevelopment and function, while its potential function in PD and neuroinflammation remains unclear. Methods: We explore the involvement of miR-218-5p in the PD in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced mouse model. The miR-218-5p agomir used for overexpression was delivered into the substantia nigra (SN) by bilateral stereotaxic infusions. The loss of dopaminergic (DA) neurons and microglial inflammation in the SN was determined using Western blotting and immunofluorescence. Motor function was assessed using the rotarod test. RNA sequencing (RNA-seq) was performed to explore the pathways regulated by miR-218-5p. The target genes of miR-218-5p were predicted using TargetScan and confirmed using dual luciferase reporter assays. The effects of miR-218-5p on microglial inflammation and related pathways were verified in murine microglia-like BV2 cells. To stimulate BV2 cells, SH-SY5Y cells were treated with 1-methyl-4-phenylpyridinium (MPP+) and the conditioned media (CM) were collected. Results: MiR-218-5p expression was reduced in both the SN of MPTP-induced mice and MPP+-treated BV2 cells. MiR-218-5p overexpression significantly alleviated MPTP-induced microglial inflammation, loss of DA neurons, and motor dysfunction. RNA sequence and gene set enrichment analysis showed that type I interferon (IFN-I) pathways were upregulated in MPTP-induced mice, while this upregulation was reversed by miR-218-5p overexpression. A luciferase reporter assay verified that Ddx41 was a target gene of miR-218-5p. In vitro, miR-218-5p overexpression or Ddx41 knockdown inhibited the IFN-I response and expression of inflammatory cytokines in BV2 cells stimulated with MPP+-CM. Conclusions: MiR-218-5p suppresses microglia-mediated neuroinflammation and preserves DA neurons via Ddx41/IFN-I. Hence, miR-218-5p-Ddx41 is a promising therapeutic target for PD. [ABSTRACT FROM AUTHOR]

The tribological behavior of traditional oil-in-water (O/W) lubricants (1.0 wt.%) and nano-TiO2 additive lubricants (1.0–9.0 wt.%) during micro rolling of titanium foils were analyzed. In this study, the surface morphologies of titanium foils under various lubrication conditions were assessed, and the corresponding lubrication mechanisms were revealed. The tribological behavior of nano-TiO2 additive lubricants during micro rolling of titanium foils was also explored through a series of characterization methods. The utilization of nano-TiO2 additive lubricants in micro rolling reduces the surface roughness of titanium foils. Moreover, it effectively inhibits the generation of indentations and cracks during rolling processes, enhancing the surface quality of rolled specimens. Additionally, owing to the synergism of rolling, tribo-film, mending and polishing effects of the nanoparticles, both the rolling force and surface roughness were minimized by using lubricants containing 3.0 wt.% TiO2 nanoparticles. Overall, an optimal concentration (3.0 wt.%) of TiO2 nanoparticles in water-based nanolubricants was obtained with enhanced tribological properties and lubrication performance during micro rolling of titanium foils. [ABSTRACT FROM AUTHOR]

Corrugated rolling is one of the metal forming processes using corrugated rolls to machine hard-to-deform metals, which leads to problems of high friction and severe wear. Lubricants are essential to reduce rolling forces, extend the life of corrugated rolls, and improve efficiency. In this work, a comparison of the surface quality of copper plates after corrugated rolling adopting different lubrication conditions (dry condition, O/W lubricant, TiO2 water-based nanolubricants) was made to explore the tribological behavior and lubricant mechanism of water-based nanolubricant during the corrugated rolling of copper plates. The results show that the 3.0 wt.% water-based nanolubricant exhibits excellent lubrication performance, and the maximum rolling force is reduced by 21.49% compared with the dry condition. Additionally, the effect of reduction on the surface quality of corrugated rolled copper plates was explored. The surface roughness at the peak position of the copper plate increased gradually with increasing reduction, and the surface roughness at the trough position showed little change, which was mainly caused by the synergistic effect of the roughness transfer and the high-strain hardening at the trough position of the copper plate. Overall, an optimal concentration of 3.0 wt.% water-based nanolubricant exhibits the best properties in terms of reducing the rolling forces and improving the surface quality of the rolled copper plates during corrugated rolling processes. [ABSTRACT FROM AUTHOR]

During past decades, water-based and oil-in-water (O/W) based nanolubricants with nanoparticles (NPs) as additives have been developed to replace conventional oil-based lubricants for solving contamination problems during rolling processes. The formulations of nanolubricants for rolling need to be continuously improved to provide better lubrication performance. This article reviews the formulation, physicochemical properties, and lubrication mechanisms during rolling with water-based and O/W based nanolubricants, and the effects of nanolubricants on rolling force, surface roughness and oxide skin formation during rolling are discussed. This review aims to facilitate the fundamental understanding of nanolubrication and the development of rolling lubrication technology. [ABSTRACT FROM AUTHOR]

Context: In this paper, the electronic and optical properties of Cr-doped monolayer MoS2 under uniaxial tensile strain are investigated by first-principle calculations. It is shown that uniaxial tensile strain can significantly change the electronic and optical properties of Cr-doped monolayer MoS2, and the bandgap value of the intrinsic MoS2 system gradually decreases with the increase of tensile strain, while the bandgap value of the Cr-doped MoS2 system is relatively stable. However, when the stretching reaches a certain degree, both the intrinsic and doped systems become metallic. From the analysis of the density of states, it is found that new electronic states and energy levels appear in the intrinsic MoS2 system and all Cr-doped monolayer MoS2 systems with the increase of the tensile strain, but the changes in the density of states diagrams of the Cr-doped monolayer MoS2 system are relatively small, which is mainly attributed to the effect of the Cr-doped atoms. The analysis of optical properties displays that the stretched doped system differs from the intrinsic MoS2 system in terms of dielectric function, absorption and reflection, energy loss function, and refractive index. Our results suggest that uniaxial tensile strain can be used as an effective means to modulate the electronic structure and optical properties of Cr-doped monolayer MoS2. These findings provide a theoretical basis for understanding the optoelectronic properties of MoS2 and its doped systems as well as their applications in optoelectronic devices. Methods: Based on the first principle of density functional theory framework and the CASTEP module in Materials Studio software (Perdew et al. in Phys Rev Lett 77(18):3865–3868, 1996). The structure of Cr atom-doped MoS2 systems and MoS2 systems were optimized using the generalized gradient approximation plane-wave pseudopotential method (GGA) and Perdew-Burke-Ernzerhof (PBE) generalized functions under 3%, 6%, and 9% tensile deformation, and the corresponding formation energy, bond length, electronic structure, and optical properties of the models were analyzed. The Grimme (J Comput Chem 27(15):1787–1799, 2006) vdW correction with 400 eV cutoff was used in Perdew-Burke-Ernzerhof (PBE) functional to optimize the geometry until the forces and energy converged to 0.02 eV/Å and 1.0e-5eV/atom, respectively. For each model structure optimization, the K-point grid was assumed to be 4×4×1, using the Monkhorst-Pack special K-point sampling method. After the MoS2 supercell convergence test, the plane-wave truncation energy was chosen to be 400 eV. Following geometric optimization, the iterative accuracy converged to no less than 1.0×10−5 eV/atom for total atomic energy and less than 0.02 eV/Å for all atomic forces. We created a vacuum layer of 18 Å along the Z-axis to prevent the impact of periodic boundary conditions and weak van der Waals forces between layers on the monolayer MoS2. In this paper, a total of 27 atoms were used for the 3×3×1 supercell MoS2 system, which consists of 18 S atoms and 9 Mo atoms. [ABSTRACT FROM AUTHOR]

Spark plasma sintering (SPS) is a powerful technique for consolidating metal powders at a remarkably shorter time with excellent quality. We used this technique for sintering nanocrystalline WC10Co powders and simultaneously bonding with high-strength steel. A series of experiments were conducted in order to find out the optimised set of SPS controlling parameters. The effects of temperatures (1000 to 1150 °C, with a 50 °C interval) in sintering nanocrystalline WC10Co powders and their bonding phenomena with AISI4340 steel were examined at a constant pressure of 80 MPa and a holding time of 5 min. The full density of the carbide powders was achieved at a lower temperature compared with that of conventional techniques. A number of techniques were employed to evaluate the microstructural characteristics of WC and steel bilayered composite and their mechanical properties. For determining the bonding strength of the joint, a novel micro-tensile testing system was adopted. Since such investigation is the first of its kind, to the best knowledge of the authors, where SPS is used to join the tungsten carbide with the steel, this research is expected to provide a valuable future reference for fabricating dissimilar bilayered composite materials. [ABSTRACT FROM AUTHOR]

Lithium‐ion batteries (LIBs) have dominated the secondary batteries market in the past few decades. However, their widespread application is seriously hampered by the limited lithium resource and high cost. Recently, sodium‐ion batteries (SIBs) have generated significant attention because of their characteristics of abundant raw sources, low cost, and similar "rocking chair" mechanism with LIBs, which hold great application potential in large‐scale energy storage. Cathode materials with excellent electrochemical performance are in urgent demand for next‐generation SIBs. Herein, this review provides a comprehensive overview of the recent advances of the most promising SIBs cathode candidates, including layered oxides, polyanionic materials, and Prussian blue analogues. The currently existing issues that need to be addressed for these cathodes are pointed out, such as insufficient energy density, low electron conductivity, air sensitivity, and so on. This review also details the structural characteristics of these three cathode candidates. Moreover, the recent optimization strategies for improving the electrochemical performance are summarized, including element doping, morphology modification, structure architecture, and so on. Finally, the current research status and proposed future developmental directions of these three cathode materials are concluded. This review aims to provide practical guidance for the development of cathode materials for next‐generation SIBs. [ABSTRACT FROM AUTHOR]

The ceramics with the formula of Sr1−xSm2x/3TiO3 (x = 0‐0.5) were prepared by conventional ceramic process. A single phase of SrTiO3‐type with cubic perovskite structure was found companied with a decrease in crystal volume when x < 0.5, which was confirmed by X‐ray diffraction results and Rietveld refine. At the level of x = 0.5, the sample consisted of two phases of SrTiO3‐type and Sm2Ti2O7. Raman spectra were used to confirm the change of vibration to explain the variation in microwave dielectric properties. The dielectric constant decreased, the quality factor increased, and the temperature coefficient shifted negatively, when the x value increased from 0 to 0.4. When the x value located between 0.3 and 0.4, the ceramics exhibited high dielectric constant of 140‐152, high quality factor (>6000). [ABSTRACT FROM AUTHOR]

In this study, the effect of cold rolling reduction ratio (CRRR) on the microstructure and mechanical properties of ferritic stainless steel (FSS) 430 were analyzed based on a series of experiments. The results show that the thickness of coarse grain bands decreases with an increase in CRRR, and when the CRRR increases to a certain value, the coarse grain bands break down into refined, equiaxed grains due to the plastic deformation. In addition, the optimization of CRRR was found to benefit both the microstructural refinement and mechanical properties of FSS 430. Also, the optimization of CRRR optimized the texture structure of FSS 430 by reducing the fraction of undesired components ({110} < 110 > component, for example), giving a rise to the plasticity of material. On the other hand, the formation of Lüders band can also be affected by the modification of CRRR. Overall, an optimal CRRR of 70% was obtained with refined microstructure and texture structure, thereby improving the mechanical properties of FSS 430. [ABSTRACT FROM AUTHOR]

Background: Donkey meat has low fat and high protein contents and is rich in various unsaturated fatty acids and trace elements that are beneficial to human digestion and absorption. IMF (intramuscular fat), also known as marbling, is an important indicator of the lean meat to fat ratio, which directly affects the tenderness and juiciness of the meat. At present, the underlying molecular variations affecting IMF content among donkey breeds are unclear. The Guangling donkey is an indigenous species in China. This study explored candidate regulatory genes that affect IMF content in Guangling donkeys. The IMF content of the longissimus dorsi muscle in 30 Guangling donkeys was measured. Six donkeys of similar age were selected according to age factors and divided into two groups, the high (H) and low (L) fat groups, according to their IMF content. Results: RNA-seq technology was used to compare the muscle transcriptome between the two groups. More than 75.0% of alternative splicing (AS) events were of the skipped exon (SE) type. A total of 887 novel genes were identified; only 386 novel genes were aligned to the annotation information of various databases. Transcriptomics analysis revealed 167 differentially expressed genes (DEGs), of which 64 were upregulated and 103 were downregulated between the H and L groups. Gene ontology analysis showed that the DEGs were enriched in multiple biological processes and pathways that are related to adipocyte differentiation, lipid synthesis, and neutral lipid metabolism. KEGG pathway analysis suggested that arachidonic acid metabolism, the HIF-1 signalling pathway, fructose and mannose metabolism, glycerophospholipid metabolism, and the AMPK signalling pathway were involved in lipid deposition. In addition, a gene–gene interaction network was constructed that revealed that the DEGs, including SCD, LEPR, CIDEA, DLK1, DGAT2, ITGAL, HMOX1, WNT10B, and DGKA, had significant roles in adipocyte differentiation and adipogenesis. The selected DEGs were further validated by qRT–PCR. Conclusion: This study improves the in-depth understanding of gene regulation and protein expression regarding IMF deposition and lays a basis for subsequent molecular breeding studies in Guangling donkeys. [ABSTRACT FROM AUTHOR]

• Crystal plasticity finite element model exhibits higher accuracy in evaluation of surface roughness and thickness distribution of cups fabricated by micro deep drawing. • The magnitude of surface roughness S z is almost linearly dependent on the average grain size of austenitic stainless steel foils. • The brass components are beneficial to the formation of drawn cups with uniform thickness distribution and the absence of severe defects. The present work involves the numerical simulation and experimental study on the surface roughness evolution and heterogeneous plastic deformation (strain localization and concomitant surface morphology evolution) in grain scale of micro deep drawn parts of austenitic stainless steel (ASS) 304 foils. A three-dimensional modeling framework was used to simulate the micro deep drawing (MDD) process. The simulation involved the development of a Voronoi-based polycrystalline geometry model (VPGM), a multi-stress-strain response model, and a crystal plasticity finite element methods (CPFEM) model. The results indicate that CPFEM model exhibits higher accuracy in the localized stress and strain, thickness distribution fluctuation and surface roughness evolution of the fabricated parts compared to multi-stress-strain response model. Therefore, the plastic deformation heterogeneity in MDD is in-depth discussed based on CPFEM model. The results show that the coarse-grained foils correspond to the intense strain localization, which is the main cause of surface roughening. Considering the average grain size is close to the thickness of ASS foils, mounding features on the rough surface may readily develop further into potentially fractured sites during deformation. On the other hand, crystal orientation influence plastic deformation by affecting the slip behavior of materials. The effect of crystal orientations including {011} 〈211〉 (Brass), {011} 〈100〉 (Goss), and {112} 〈110〉 components on deformation is discussed. The results indicate a strong correlation between the magnitude of the Schmid's factor and the ease of deformation. Additionally, variations in Schmid's factor across different directions result in differences in deformation accumulation, which affects the thickness distribution along the radial direction and the distribution of earrings and wrinkles along the circumferential direction of the fabricated micro parts. [ABSTRACT FROM AUTHOR]

Electron backscatter diffraction (EBSD) analysis has been presented to investigate the microstructure and microtexture evolutions of deformed oxide scale formed on a microalloyed steel during hot rolling and accelerated cooling. Magnetite and wustite in oxide layers share a strong {0 0 1} and a weak {1 1 0} fibres texture parallel to the oxide growth. Trigonal hematite develops the {0 0 0 1} basal fibre parallel to the crystallographic plane {1 1 1} in magnetite. Taylor factor estimates have been conducted to elucidate the microtexture evolution. The fine-grained magnetite seam adjacent to the substrate is governed by stress relief and ions vacancy diffusion mechanism. [ABSTRACT FROM AUTHOR]

A 3D elastic-plastic finite element method (FEM) model of cold strip rolling for 6-high continuous variable crown (CVC) control rolling mill was developed. This model considers the boundary conditions such as accurate CVC curves, total rolling forces, total bending forces and roll shifting values. The rolling force distributions were obtained by the internal iteration processes instead of being treated as model boundary conditions. The calculated error has been significantly reduced by the developed model. Based on the rolling schedule data from a 1,850-mm CVC cold rolling mill, the absolute error between the simulated results and the actual values is obtained to be less than 10 μm and relative error is less than 1 %. The simulated results are in good agreement with the measured data. The developed model is significant in investigating the flatness control capability of the 6-high CVC cold rolling mill in terms of work roll bending forces, intermediate roll bending forces and intermediate roll shifting values. [ABSTRACT FROM AUTHOR]

Highlights: [•] The oxidation behaviour of the Nb–V–Ti microalloyed steel is investigated. [•] The coarse-grained steel substrate has detrimental effect on adhesion properties. [•] High magnetite content is attributed to grain-boundary oxidation above 570°C. [•] Grain refinement mechanism is proposed to generate the tight oxide scale. [ABSTRACT FROM AUTHOR]

AbstractBrains undergo significant remodeling after traumatic brain injury (TBI). The Rho guanine triphosphate (GTP)ase pathways control brain remodeling during development and under pathological conditions. How the Rho GTPase pathways are regulated in the brain after TBI remains largely unknown, however. This study used the rat fluid percussion injury model to investigate changes in the Rho GTPase pathways after TBI. The results showed that TBI leads to activation and translocation of RhoA and Rac1 proteins from cytosolic fraction to the membrane fraction after injury. Consistently, the Rho guanine nucleotide exchange factors GEF-H1 and Cool-2/αPix are significantly activated by dephosphorylation and accumulation in the cytosolic fractions during the post-TBI phase. Because the Rho GTPase pathways are key regulators of brain remodeling, these results depict regulatory mechanisms of the Rho GTPase pathways after TBI, and pave the way for the study of therapeutic agents targeting the Rho GTPase pathways for functional recovery after TBI. [ABSTRACT FROM AUTHOR]

• Study of roof cutting parameters for soft-rock coal pillar mining roadway. • A similar rock bolt-mesh-cable-strip-shotcrete roadway is built as a simulation model. • The protection mechanism of roof-cutting to the front roadways are studied. • The stability of mining roadway can also be improved without adding support members. In the confinement of traditional supports, reinforced supports are often used to control the deformation of roadways constructed in soft rock. Due to the failure to weaken the factors that induce deformation at the source, the roadway remains damaged after the restoration period. To this end, taking inspiration from roof cutting and pressure relief concepts, the protection mechanism of stress transfer in mining roadways constructed in soft rock of longwall remaining coal pillars was studied in the context of a typical coal mine. Unlike the technical scheme of gob-side entry retaining, no components are added in this study. The roof cutting and coal mining progress are consistent to ensure the integrity of the roadway in front of the longwall coal mining face (LCMF). The effect of the roof-cutting parameter on the roadway is studied via numerical simulations, and the optimal parameters are subsequently applied to similar material simulation experiments. It was found that roof cutting relieved the mechanical connection between the gob roof and the roadway roof, and the high-stress area was transferred from the roadway roof to the front of the LCMF. Roof cutting diminished the abutment stress in the surrounding rock in the area of intense dynamic pressure in front of the LCMF (average reduction of 12.57 %), which effectively improved the stability of the roadway. The roof cutting impaired the traction effect of the roadway roof deformation behind the LCMF on the strata ahead and effectively reduced the roadway deformation (27.3 % reduction) and coal pillar deformation (15.7 % reduction). On-site practice has demonstrated the effectiveness of this research, and the results of this research provide a new idea for preventing the destruction of roadways constructed in soft rock. [ABSTRACT FROM AUTHOR]

Background and Purpose: Shikonin was reported to induce necroptosis in leukemia cells, but apoptosis in glioma cell lines. Thus, it is needed to clarify whether shikonin could cause necroptosis in glioma cells and investigate its underlying mechanisms. Methods: Shikonin and rat C6 glioma cell line and Human U87 glioma cell line were used in this study. The cellular viability was assayed by MTT. Flow cytometry with annexin V-FITC and PI double staining was used to analyze cellular death modes. Morphological alterations in C6 glioma cells treated with shikoinin were evaluated by electronic transmission microscopy and fluorescence microscopy with Hoechst 33342 and PI double staining. The level of reactive oxygen species was assessed by using redox-sensitive dye DCFH-DA. The expressional level of necroptosis associated protein RIP-1 was analyzed by western blotting. Results: Shikonin induced cell death in C6 and U87 glioma cells in a dose and time dependent manner. The cell death in C6 and U87 glioma cells could be inhibited by necroptosis inhibitor necrotatin-1, not by pan-caspase inhibitor z-VAD-fmk. Shikonin treated C6 glioma cells presented electron-lucent cytoplasm, loss of plasma membrane integrity and intact nuclear membrane in morphology. The increased ROS level caused by shikonin was attenuated by necrostatin-1 and blocking ROS by anti-oxidant NAC rescued shikonin-induced cell death in both C6 and U87 glioma cells. Moreover, the expressional level of RIP-1 was up-regulated by shikonin in a dose and time dependent manner as well, but NAC suppressed RIP-1 expression. Conclusions: We demonstrated that the cell death caused by shikonin in C6 and U87 glioma cells was mainly via necroptosis. Moreover, not only RIP-1 pathway, but also oxidative stress participated in the activation of shikonin induced necroptosis. [ABSTRACT FROM AUTHOR]

Glioma is the most common type of brain tumor and is associated with a high mortality rate. Despite recent advances in treatment options, the overall prognosis in patients with glioma remains poor. Studies have suggested that circular (circ)RNAs serve important roles in the development and progression of glioma and may have potential as therapeutic targets. However, the expression profiles of circRNAs and their functions in glioma have rarely been studied. The present study aimed to screen differentially expressed circRNAs (DECs) between glioma and normal brain tissues using sequencing data collected from the Gene Expression Omnibus database (GSE86202 and GSE92322 datasets) and explain their mechanisms based on the competing endogenous (ce)RNA regulatory hypothesis. In total, 424 commonly downregulated DECs (with the Gene_symbol annotated in the circBase database) in these two datasets were identified. Using the CircInteractome and Starbase databases, 18 micro (mi)RNAs (miRs) were predicted to interact with DECs, while 22 glioma-related genes obtained from the Comparative Toxicogenomics Database were predicted to be regulated by 15 miRNAs via the miRwalk 2.0 database. A ceRNA network was established based on 115 DECs, 15 miRNAs and 22 mRNAs. LinkedOmics online analysis using The Cancer Genome Atlas (TCGA) data showed that hsa-miR-142-3p/hsa-miR-590-5p and their target gene adenomatous polyposis coli protein (APC) were all significantly associated with overall survival rate and their prognosis trend was opposite, revealing that high expression levels of hsa-miR-142-3p/hsa-miR-590-5 were associated with a poor overall survival rate, while high APC expression with a good overall survival rate. UALCAN analysis using TCGA data of glioblastoma multiforme and the GSE25632 and GSE103229 microarray datasets showed that hsa-miR-142-3p/hsa-miR-590-5p was upregulated and APC was downregulated. Thus, hsa-miR-142-3p/hsa-miR-590-5p-APC-related circ/ceRNA axes may be important in glioma, and hsa_circ_0005114 interacted with both of these miRNAs. Functional analysis showed that hsa_circ_0005114 was involved in insulin secretion, while APC was associated with the Wnt signaling pathway. In conclusion, hsa_circ_0005114-miR-142-3p/miR-590-5p-APC ceRNA axes may be potential targets for the treatment of glioma. [ABSTRACT FROM AUTHOR]

Abstract Graphene encapsulated SiC nanoparticles were incorporated into aluminium matrix composite (AMC) and its tribological behaviour was investigated under dry sliding wear. SEM, 3D-laser, TEM and Raman microscopies were employed to characterise the composite. It was found that the wear rate and coefficient of friction of the composite were 98.0% and 35.9% lower than that of the reference sample reinforced with solely SiC nanoparticles respectively. The improved tribological properties are probably attributed to the uniform distribution of graphene nanosheets in the bulk composite which smeared on the wear scar and formed graphene-rich micro tribofilms during the sliding wear. [ABSTRACT FROM AUTHOR]

A wet ball milling route was used to synthesise SiC-graphene core-shell nanoparticles in situ from graphite and SiC nanoparticles. Graphite flakes were gradually exfoliated into fresh graphene nanosheets (GNSs) without significant defects, which is attributed to mechanical shearing and moderate impaction forces between graphite flakes, milling balls and SiC nanoparticles during the wet milling. The non-destructive exfoliation is characterised by Raman, Fourier transform infrared and X-Ray photoelectron spectroscopies. The freshly produced GNSs are energetically unstable and thin enough to be flexible and this drives the in situ attaching and scrolling of GNSs on the SiC nanoparticles. The SiC nanoparticles and GNSs are well dispersed in the wet medium and the SiC nanoparticles are individually wrapped. It has been estimated that > 50% of the produced GNSs are wrapped around the SiC nanoparticles and these GNSs are generally ≤ 6 layers. [ABSTRACT FROM AUTHOR]

This paper proposes a self-piercing riveting (SPR) method which uses a flange pipe rivet. This joining technology can solve the problems of oblique rivet and incorrect rivet position which are usually found in the SPR with a pipe rivet. The lap shear strength of the joint with a flange pipe rivet is higher than that of a joint with a conventional rivet. In this research, a flange pipe rivet was placed between two sheets with a force applied to the top sheet by a punch riveting machine. The flange pipe rivet moved downward along with the top sheet to induce appropriate bending and form a mechanical interlock in both sheets. Finite element (FE) analysis of the SPR with a flange pipe rivet was done by DEFORM software. The simulated joint cross-section shapes were observed, and the influence of the flange pipe rivet parameters on joint quality was analyzed. Simultaneously, some riveting experiments on joining aluminum sheets were conducted taking into consideration different rivet heights and chamfer angles. The results show that the joining surface is smooth and the simulated joint cross-section shapes are in good agreement with the experimental results. The joining property with a chamfer angle of 45° and a rivet height of 5 mm is found to be the best in joining the Al6063 aluminum alloy sheets with a thickness of 2.4 mm by using the SPR with a flange pipe rivet. [ABSTRACT FROM AUTHOR]

• The discrepancy of mechanical properties between ti and al layers evidences the slip bands with 45° to tensile direction in Al grains. • Morphology and/or crystallographic orientation changes in al grains of composite achieve a compatible deformation. • Heterogeneous deformation induced stress concentration facilitates the initiation of micro-crack and sequential failure at the interfacial zone. Laminated/bimetal composites can offer the advantage of combining constituent metals, but their heterogeneous microstructures exhibit different mechanical properties during subsequent remanufacturing process than those of the homogeneous counterparts. This study investigated the tensile properties, microstructural evolution and deformation behaviours of a new explosive welded TA1/5083 composite sheet using the in-situ characterisation. It is found that a wavy transition zone forms in the composite sheet, showing gradients in the element diffusion and micro-hardness adjacent to the interface. The slip bands with the tensile direction of 45° primarily occur in the 5083 side (rather than the TA1 side) with an increase in deformation. Although the dislocation density of the grains in the 5083 layer increases significantly, these grains are slightly elongated along the tensile direction without a significant orientation change. Three deformation stages and a subsequent crack initiation stage appear during the in-situ tensile process. The initiation of micro-cracks in the interfacial zone results from the internal stress concentration occurring at the bottom of interfacial wave structure. Once initial micro-cracks evolve into the intermetallic compounds (IMCs) of the interfacial zone, the high magnitude of stress concentrations of the TA1 and 5083 layers leads to necking and sequential fractures. This study can provide a reference for the design of high-quality Ti/Al composite components for industry. [Display omitted] [ABSTRACT FROM AUTHOR]

The preparation of cermet-modified layers on the surface of titanium alloys using lasers is an effective method to improve their wear resistance. In this study, a typical Ti–TiN composite cermet layer was prepared in situ on the surface of a titanium alloy by laser melting under a N 2 atmosphere. The microstructure and wear behavior were characterized. The rapid cooling of the laser and the difference in the physical and chemical properties of the ceramics and metals led to the appearance of stacking faults in the TiN ceramic phase, dislocation cells in the Ti phase, and semi-coherent interfaces with stacking fault groups as transition structures. Friction test analysis shows that the formation of the Ti–TiN cermet layer significantly improves the surface wear resistance of the titanium alloy. In particular, the wear resistance is improved by approximately one order of magnitude at 500 °C. The accumulative strengthening and stable strain hardening were formed by the deformation dislocation network in the TiN phase, polycrystalline transformation and dislocation interaction in the Ti phase. These microstructural transformations improve the wear resistance of the cermet layer. The amorphous-crystalline nanocomposite friction glaze layer formed in the wear scar at high temperatures further improves the wear scar strength, and the uniform plastic deformation during friction shear inhibits wear and balances the force distribution on both the phases during the friction process. [ABSTRACT FROM AUTHOR]

The breakaway oxidation behaviour of ferritic stainless steels 430, 443 and 445 has been investigated at 1150 °C in humid air. The oxidation kinetics exhibited significant differences among the three ferritic stainless steels. A uniform and steady growing oxide scale was developed on the 430 steel with an even steel/oxide interface. Local breakdown of the initially protective oxide scale occurred and oxide nodules were developed on the 443 and 445 stainless steels, resulting in irregular and rough steel/oxide interfaces. The breakaway oxidation behaviour was significantly influenced by the microstructure and the composition of the oxide scale. The Mn-Cr spinel oxide formed on top of the Cr 2 O 3 scale in Mo alloying 445 steel can greatly minimise the Cr depletion. [ABSTRACT FROM AUTHOR]

Parkinson's disease (PD) is characterized by impaired mitochondrial function and decreased ATP levels. Aerobic glycolysis and lactate production have been shown to be upregulated in dopaminergic neurons to sustain ATP levels, but the effect of upregulated glycolysis on dopaminergic neurons remains unknown. Since lactate promotes apoptosis and α-synuclein accumulation in neurons, we hypothesized that the lactate produced upon upregulated glycolysis is involved in the apoptosis of dopaminergic neurons in PD. In this study, we examined the expression of hexokinase 2 (HK2) and lactate dehydrogenase (LDH), the key enzymes in glycolysis, and lactate levels in the substantia nigra pars compacta (SNpc) of a MPTP-induced mouse model of PD and in MPP+-treated SH-SY5Y cells. We found that the expression of HK2 and LDHA and the lactate levels were markedly increased in the SNpc of MPTP-treated mice and in MPP+-treated SH-SY5Y cells. Exogenous lactate treatment led to the apoptosis of SH-SY5Y cells. Intriguingly, lactate production and the apoptosis of dopaminergic neurons were suppressed by the application of 3-bromopyruvic acid (3-Brpa), a HK2 inhibitor, or siRNA both in vivo and in vitro. 3-Brpa treatment markedly improved the motor behaviour of MPTP-treated mice in pole test and rotarod test. Mechanistically, lactate increases the activity of adenosine monophosphate-activated protein kinase (AMPK) and suppresses the phosphorylation of serine/threonine kinase 1 (Akt) and mammalian target of rapamycin (mTOR). Together, our data suggest that upregulated HK2 and LDHA and increased lactate levels prompt the apoptosis of dopaminergic neurons in PD. Inhibition of HK2 expression attenuated the apoptosis of dopaminergic neurons by downregulating lactate production and AMPK/Akt/mTOR pathway in PD. [Display omitted] • Aerobic glycolysis has been shown to be upregulated in PD, but the effect on dopaminergic neurons remains unknown. • Upregulated HK2 and LDHA and increased lactate are involved in the apoptosis of dopaminergic neurons. • Pharmacological suppression or genetic ablation of HK2 alleviated the apoptosis of dopaminergic neurons. • Our findings provide new insight into the pathological mechanisms underlying the pros and cons of glycolysis in PD. [ABSTRACT FROM AUTHOR]