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Abstract This study reveals two-stage wrinkling behavior of Al films deposited on polydimethylsiloxane (PDMS) substrates by magnetron sputtering at a high temperature. The hierarchical structures with nano-micro dual scale wrinkles were created in Al films. The micro-scale wrinkles originated from thermal contraction, with the wavelength increasing with increasing film thickness, while nano-scale wrinkles, with an almost unchanged wavelength, are induced by the expansion of the mixed layer on the PDMS surface. The results provide a facile method to produce the hierarchical wrinkled surfaces for functionality. Graphical abstract Unlabelled Image [ABSTRACT FROM AUTHOR]

A piezoelectric cantilever vibration energy collector (PCVEC) was developed to harvest friction-induced vibration (FIV) energy. Tests were conducted using a CETR machine. A finite element model (FEM) and a 5-degree-of-freedom (5-DOF) numerical model were established to verify the harvester's effectiveness. The results show that PCVEC effectively converts FIV energy into electrical energy. PCVEC does not generate any voltage when the block moves in the direction opposite to the friction direction. PCVEC exhibits better deformation capability when the mass and stiffness of cantilever beam are low, enabling the piezoelectric ceramic material to convert FIV energy into electrical energy more efficiently. As the mass and stiffness increase, the deformation capability of the PCVEC weakens, resulting in a decrease in the output voltage. • Effectiveness of PCVEC in harvesting FIV energy and its influencing factors were studied via experiments and simulations. • A finite element model and a 5-degree-of-freedom numerical model with a PCVEC were established. • Effect of cantilever beam structural parameters on the output voltage of PCVEC was discussed. • Deformation capability of cantilever beam determines the effectiveness of FIV energy harvesting by PCVEC was discovered. [ABSTRACT FROM AUTHOR]

Abstract The strength and plasticity of metallic materials usually exhibit a trade-off relation. This study reports a simultaneous improvement in the ultimate tensile strength (UTS) and uniform elongation (UE) of Ti-24Nb-4Zr-8Sn (Ti2448) fabricated by selective laser melting (SLM), relative to those produced via forging. Detailed microstructural characterization reveals that the outstanding tensile property may result from the bi-model structure that forms during the rapid cooling associated with SLM. Coarse grains are surrounded by fine grains within the melt pool, which causes a back stress during tension. The back stress provides additional strain-hardening capacity, which postpones the initiation of necking and then leads to the simultaneous improvement of the strength and plasticity (SISP) of the Ti2448 alloy. Furthermore, the tensile property of the SLM-fabricated sample is anisotropic which is strongly related to the irregular shape of the melt pool. Graphical abstract Unlabelled Image Highlights • Melt pools with a bi-model structure are formed in a biocompatible Ti alloy through selective laser melting. • The as-built Ti alloy exhibits a better combination of strength and plasticity, relative to traditionally forged counterpart. • For the first time, the back stress of the melt pool along different directions is studied through finite element modelling. [ABSTRACT FROM AUTHOR]

The friction block height of high-speed trains decreases with service time. However, the influence of height on friction-induced vibration and noise (FIVN) is unclear. Therefore, we conducted friction braking tests of blocks with different heights. A finite element model and a numerical model were established to evaluate the structure and motion characteristics of the block and the effects of its height on FIVN. The results show that blocks with greater height exhibit greater eccentric wear, resulting in stronger FIVN. The block inclined state causes contact pressure to concentrate at the leading edge, which is the main cause of eccentric wear. The block height, the inclination angle, and the resulting eccentric wear significantly affect the braking system stability and FIVN characteristics. [ABSTRACT FROM AUTHOR]

β-type titanium porous structure is a new class of solution for implant because it offers excellent combinations of high strength and low Young's modulus. This work investigated the influence of porosity variation in electron beam melting (EBM)-produced β-type Ti2448 alloy samples on the mechanical properties including super-elastic property, Young's modulus, compressive strength and fatigue properties. The relationship between the misorientation angle of adjacent grains and fatigue crack deflection behaviors was also observed. The super-elastic property is improved as the porosity of samples increases because of increasing tensile/compressive ratio. For the first time, the position of fatigue crack initiation is defined in stress-strain curves based on the variation of the fatigue cyclic loops. The unique manufacturing process of EBM results in the generation of different sizes of grains, and the apparent fatigue crack deflection occurs at the grain boundaries in the columnar grain zone due to substantial misorientation between adjacent grains. Compared with Ti-6Al-4V samples, the Ti2448 porous samples exhibit a higher normalized fatigue strength owing to super-elastic property, greater plastic zone ahead of the fatigue crack tip and the crack deflection behavior. [ABSTRACT FROM AUTHOR]

Objectives Low modulus β-titanium alloys with non-toxic alloying elements are envisaged to provide good biocompatibility and alleviate the undesired stress shielding effect. The objective of this study is to fundamentally elucidate the biological response of novel high strength-low elastic modulus Ti2448 alloy through the study of bioactivity and osteoblast cell functions. Methods Characterization techniques such as SEM, EDX, XRD, and fluorescence microscopy were utilized to analyze the microstructure, morphology, chemical composition, and cell adhesion. The cellular activity was explored in terms of cell-to-cell communication involving proliferation, spreading, synthesis of extracellular and intracellular proteins, differentiation, and mineralization. Results The formation of fine apatite-like crystals on the surface during immersion test in simulated body fluid confirmed the bioactivity of the surface, which provided the favorable osteogenic microenvironment for cell-material interaction. The proliferation and differentiation of pre-osteoblasts and their ability to form a well mineralized bone-like extracellular matrix (ECM) by secreting bone markers (ALP, calcium, etc.) over the surface point toward the determining role of unique surface chemistry and surface properties of the Ti–24Nb–4Zr–8Sn (Ti2448) alloy in modulating osteoblasts functions. Significance These results demonstrated that the low modulus (∼49 GPa) Ti2448 alloy with non-toxic alloying elements can be used as a potential dental or orthopedic load-bearing implant material. [ABSTRACT FROM AUTHOR]

Abstract: A multifunctional titanium alloy Ti–24Nb–4Zr–8Sn (wt%) was fabricated by warm swaging and rolling to get homogeneous microstructure with ultrafine-grained (UFG) β phase and nanostructured (NS) α phase, and their stress-controlled high cycle fatigue (HCF) and strain-controlled low cycle fatigue (LCF) behaviors were investigated in the study. The results showed that the UFG alloy exhibits much higher HCF strength than that of the hot-rolled alloy with coarse grains whereas its LCF endurance is worse slightly. This was explained by its stable microstructure originated from low homologous temperature being ∼0.15 of melting temperature and the improvement of phase stability by grain refinement and NS precipitations. The former leads to dynamic recovery instead of dynamic recrystallization occurring in other UFG materials while the latter results in comparable cyclic stress stability with the hot-rolled alloy. The study also found that the shear bands have an identical angle of ∼26° with the loading direction, which is independent of the strain ratios. Since the ductile UFG alloy has a nonlinear elastic deformation behavior with large recoverable strain, its LCF endurance is much better than those of other materials exhibiting linear elasticity and would be further improved by the depression of NS precipitation. [Copyright &y& Elsevier]

Abstract: A combination processing technique of warm swaging and warm rolling is proposed to refine grains and improve the mechanical properties of a multifunctional β-type Ti–24Nb–4Zr–8Sn (wt.%) alloy. The results show that a highly swirled marble-like microstructure can be easily produced by warm swaging at an initial temperature of 573K, whereas it has little effect on the nonlinear elastic deformation compared with the hot forged alloy with an equiaxed microstructure. Although the swirled microstructure has the limitation of an inhomogeneous distribution, swaging has the great advantage of refining the initial subgrains produced by hot forging with little loss of ductility. The following warm rolling at an initial temperature of 673K results in a uniform microstructure comprising β phase with a size less than ∼200nm and the precipitation of nanosized α phase. Therefore, significant grain refinement was achieved through the formation and refinement of the subgrains. The ultrafine grained alloy exhibits large scale nonlinear deformation behavior with a recoverable strain of up to ∼3.4% in combination with a high strength of ∼1150MPa, a low elastic modulus of ∼56GPa and good ductility of ∼8%. Such an improvement in mechanical properties indicate great potential for biomedical applications. [Copyright &y& Elsevier]

Abstract: Cu reticulated mesh and stochastic open cellular foams were fabricated by additive manufacturing using electron beam melting. Fabricated densities ranged from 0.73g/cm3 to 6.67g/cm3. The precursor Cu powder contained Cu2O precipitates and the fabricated components contained arrays of Cu2O precipitates and interconnected dislocation microstructures having average spacings of ∼2μm, which provide hardness values ∼75% above commercial Cu products. Plots of stiffness (Young''s modulus) versus density and relative stiffness versus relative density were in very close agreement with the Gibson–Ashby model for open cellular foams. These open cellular structure components exhibit considerable potential for novel, complex, multi-functional electrical and thermal management systems, especially complex, monolithic heat exchange devices. [Copyright &y& Elsevier]

The impact behavior of the Ti–6Al–4V alloy has been investigated at varying temperatures (298 K, 223 K, 77 K) in this study. The results reveal a decrease in toughness with reduced temperature, with notable changes in energy distribution between crack initiation and propagation. The { 10 1 ¯ 2 } α twins formed in the studied sample under impact loading at 298 K and 223 K, and were absent at 77 K. The formation and propagation of twins contribute to the higher toughness of the 298 K and 223 K samples. These findings would provide valuable guidance to optimize the Ti–6Al–4V alloy toughness in low-temperature environments. • The study explores how the impact toughness of Ti-6Al-4V alloy decreases with lowering temperature. • Twin formation at 298K and 223K increases the impact toughness, while no twin is observed at 77K. • Twin transfer behavior influenced by misorientation angle increases the impact toughness. [ABSTRACT FROM AUTHOR]

Abstract: Owing to the large band gap energy of 3.2eV, pure TiO2 film operates as an efficient photocatalyst under UV light irradiation and exhibits no photocatalytic activity under the visible spectral region. UV is only about 3% of the light existing in the solar spectrum. Currently, the red-shift in the band gap energy induced by dye-modified TiO2 film is one of the most popular and economic processes for improving the drawback in TiO2 photocatalyst. Therefore, we assess the photocatalytic efficiency of dye-modified TiO2 thin film using various dye molecules such as Eosin Y, Safranine O and tris-2, 2′-bipyridyl dichlororuthenium (II) hexahydrate (Rubpy) using the sol–gel process under visible light (λ >400 nm). These results showed that TiO2 thin film modified with Safranine O dye had the best photodegrading efficiency under visible light irradiation. The photocatalytic inactivation of Safranine O and Eosin Y dye-modified TiO2 thin films against phytopathogenic bacteria including Enterobacter cloacae SM1 and Erwinia carotovora subsp. carotovora 3 which cause severe soft/basal rot disease in vegetable crops in Taiwan were all more than 90% after irradiation with visible light for 60min. The evidence suggests that the dye-modified TiO2 thin film under visible light irradiation has potential for plant protection applications in hydroponic systems. [Copyright &y& Elsevier]

Temperature-coefficient of resistivity (TCR) is positive for most metallic materials but negative for semiconductors. Since a Ti-Nb-based titanium alloy exhibits a negative TCR, this inspires us to tune its TCR from negative to positive by a decomposition-induced compositionally-modulated dual-phase microstructure. Here reports a continuously tunable TCR obtained by aging treatments at 723 K. The results demonstrate that a near-zero TCR over a wide temperature of 350 K is available via 0.5 h aging while its TCR varies almost linearly with the volume fraction of α" phase in the plate-like modulated microstructure. Aided by a mixture rule modeling, the tunable TCR can be quantitatively characterized by the β + α" dual-phase compositionally-modulated microstructure induced by aging treatment. These findings provide a new avenue for exploring novel temperature-independent properties by tuning spinodal decomposition. [Display omitted] • Compositionally-modulated microstructure is tuned by aging treatment in a spinodal decomposition titanium alloy. • The temperature-coefficient of resistivity varies from negative, via zero, to positive continuously. • A temperature-independent resistivity over a wide temperature range of ∼350 K is achieved. • The temperature coefficients of the α" and β phases are estimated by mixture rule modeling. [ABSTRACT FROM AUTHOR]

A martensitic transformation (MT) is a typical first-order diffusionless crystal structural change with strong autocatalysis like avalanche at a speed of sound propagation. This unique characteristic, however, is undetectable in some multifunctional titanium alloys. Recently, a nano-scale elastically confined MT mechanism was proposed because a nano-scale Nb modulation in a Ti-Nb based alloy was observed. Here we analyze the elastic confinement in details and its induced novel properties in a wide temperature range. The statistical analyses of atom probe tomography (APT) data confirm the existence of the nano-scale Nb concentration modulation. The synchrotron X-ray diffraction (SXRD) profiles demonstrate that the nano-scale Nb modulation causes weak diffuse scattering, as evidenced by the extreme broad diffraction bands. The tensile tests find a critical temperature of ∼150 K, where the critical stress to induce the MT and Young's modulus reach the minimum and the superelastic strain reaches the maximum (∼4.5%) and keeps constant as the temperature decreases further to <4.2 K. To reveal these abnormal behaviors of the MT, the Born criterion governing the elastic stability of cubic crystal is modified by introducing an elastic confinement term and a new Clausius-Clapeyron relationship is established to evaluate the elastically confined MT. The results are consistent with the experimental findings, including the solely stress-induced (no thermally induced) reversibility. [ABSTRACT FROM AUTHOR]

We elucidate here the osteoblasts functions and cellular activity in 3D printed interconnected porous architecture of functionally gradient Ti-6Al-4V alloy mesh structures in terms of cell proliferation and growth, distribution of cell nuclei, synthesis of proteins (actin, vinculin, and fibronectin), and calcium deposition. Cell culture studies with pre-osteoblasts indicated that the interconnected porous architecture of functionally gradient mesh arrays was conducive to osteoblast functions. However, there were statistically significant differences in the cellular response depending on the pore size in the functionally gradient structure. The interconnected porous architecture contributed to the distribution of cells from the large pore size (G1) to the small pore size (G3), with consequent synthesis of extracellular matrix and calcium precipitation. The gradient mesh structure significantly impacted cell adhesion and influenced the proliferation stage, such that there was high distribution of cells on struts of the gradient mesh structure. Actin and vinculin showed a significant difference in normalized expression level of protein per cell, which was absent in the case of fibronectin. Osteoblasts present on mesh struts formed a confluent sheet, bridging the pores through numerous cytoplasmic extensions. The gradient mesh structure fabricated by electron beam melting was explored to obtain fundamental insights on cellular activity with respect to osteoblast functions. [ABSTRACT FROM AUTHOR]

The deflection of cracks in grain interior was observed in a metastable β -phase Ti alloy (Ti-24Nb-4Zr-7.9Sn) with transmission electron microscopy during high cycle fatigue. This peculiar phenomenon is induced by the β → α″ martensitic transformation in front of crack tips in grain interior when cracks propagate along the {011} β slip planes with acute angles between α″ lamellae and cracks approximately of 45°. The α″ product phase has lattice dilation and contraction along two main transformation directions, thus introduces compressive and tensile strains perpendicular and parallel to crack propagating planes, respectively. This exerts beneficial effect on the crack deflection during the subsequent cyclic-loading. [ABSTRACT FROM AUTHOR]

We report a systematic study on the crystal growth of CuFe 1− x Ga x O 2 ( x =0, 0.035, 0.08, and 0.12) by using an optical floating-zone method. High-quality single crystals are successfully obtained and the growth conditions are carefully optimized. It is found that there is a wide region to set the heat power for crystallizing, but the best crystallization requires carefully adjusting the heat power. X-ray diffraction data demonstrate the good crystallinity of these crystals. The basic physical properties of these crystals are characterized by the magnetic susceptibility and thermal conductivity measurements. [ABSTRACT FROM AUTHOR]

In recent years, biochar, a porous carbon-based material, has gained attention for its application prospects in contaminated soil remediation and soil improvement. Biochar-derived organic matter has a key role in influencing the migration and transformation of soil elements and pollutants. However, existing research concerning the molecular characteristics of biochar-derived organic matter is limited. Here, we used four polar solvents — dichloromethane (CH 2 Cl 2), acetone (CH 3 COCH 3), methanol (CH 3 OH), and distilled water (H 2 O) — to extract organic matter from soybean straw biochar and wheat straw biochar by accelerated solvent extraction (ASE). We characterized the extracts using Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR-MS). We found considerable differences in organic matter according to the extraction solvents; such differences were related to the polarity of the solvent, as well as intermolecular forces between the solvent and organic matter. CH 3 OH extracted the most biochar-extractable organic matter components because CH 3 OH can weaken or destroy oxygen bridge bonds in biochar and form hydrogen bonds with small-molecule organic compounds. CH 3 OH and H 2 O have strong extraction capacity for compounds containing heteroatoms. CH 2 Cl 2 -extractable organic matter is relatively labile and bioavailable, while CH 3 OH- and H 2 O-extractable organic matters are relatively stable. In addition, the binding capacity of biochar-derived organic matter for minerals and pollutants differed among fractions, in part because of differences in molecular weight, atomic O/C and H/C ratios, heteroatom distribution, and biomolecular compounds present in biochar-derived organic matter. The findings in this study help to select appropriate extractants to analyze biochar-derived organic matter for various research purposes, and provides a theoretical basis for biochar-based remediation of contaminated soil. [Display omitted] • FT-ICR-MS was used to reveal characteristics and possible environmental behavior of BEOM at the molecular level. • The difference in BEOM was related to the polarity of extractant and intermolecular force between the extractant and organic matter. • CH 3 OH can extract the most BEOM components, CH 3 OH and H 2 O have strong extraction capacity for heteroatom compounds. • CH 2 Cl 2 -extractable organic matter is relatively labile and easily biodegraded. [ABSTRACT FROM AUTHOR]

The hydrogen-induced cracking (HIC) and blistering behaviour of A537 steel was investigated by electrochemical hydrogen permeation measurements, electrochemical hydrogen-charging tests, and surface characterisation techniques. The results indicate that at ambient temperatures the diffusivity of hydrogen in A537 steel varies along three perpendicular directions. The diffusivity of hydrogen along the through-surface ( S ) direction was observed to be lower than that along each of the other two directions. The hydrogen concentration of A537 steel increased with increasing charging current density, which promoted the HIC susceptibility of the A537 steel. HIC initiated primarily at the interface of ferritic/pearlitic bands and nucleated at non-metallic inclusions in the A537 steel. [ABSTRACT FROM AUTHOR]

In this work, the martensitic transformation occurring in the superelastic Ti–24Nb–4Zr–8Sn alloy was investigated by tensile tests, in situ synchrotron X-ray diffraction (SXRD) and dynamic mechanical analysis (DMA). The SXRD results clearly showed the diffraction peaks related to the α″ and β phases and their evolution, under loading and unloading conditions, have highlighted the reversible stress-induced martensitic (SIM) transformation. Consequently, a three step deformation sequence was established from both SXRD analysis and tensile test characterization. On the other hand, the characteristic temperatures related to the martensitic transformation under different applied stresses have been determined from the storage modulus and the damping curves by DMA analysis. Very good accordance concerning the critical stress inducing the martensitic transformation was obtained by comparing the results obtained from SXRD, DMA and tensile tests. [ABSTRACT FROM AUTHOR]

Spinodal decomposition mechanism is well-known for producing nanoscale modulated microstructure which is either sponge-like or plate-like. Our recent investigations of a Ti-Nb based titanium alloy have found two kinds of decomposition-induced transitions triggered simultaneously, a microstructural transition from the spongy-like to the plate-like and a crystal structure transition from bcc to hcp via the coupled atomic shear and shuffle mechanism along the Burgers pathway. Here focuses on thermal evolution kinetics of both transitions and their quantitative relations. Small angle neutron scattering profiles reveal that the aging treatments lead to a gradual change from an oval pattern to a butterfly pattern due to the spongy-to-plate microstructural transition. To characterize the crystal transition and its induced habit plane change, we define an ordering parameter from the shear component of the bcc-hcp transition. The results reveal that both follow the well-known power-law approximation with an activation energy of ∼209 kJ/mol, which is identical with diffusion energy of Nb in binary Ti-Nb alloy. However, their time exponential factors are different, about 1/5 for the microstructure growth and 1/16 for the crystal ordering and its induced habit plane change. The former is less than the common 1/3 law of the decomposition mechanism and the nucleation and growth mechanism. Aided by these kinetic equations, the microstructural and chemical parameters can be modeled by the crystal ordering. This provides a new strategy to tune the nanoscale microstructure by this novel spinodal decomposition coupled with a continuous crystal ordering. [Display omitted] [ABSTRACT FROM AUTHOR]

Based on detailed first-principles investigations of the hexagonal antidot patterned graphene nanomeshes, we have studied the mechanisms of the conducting property modification of graphene. The band-folding analysis shows that the (3 n ,3 m ) ( n and m are integers) superlattice would have fourfold degeneracy at Г point. An effective method by removing this fourfold degeneracy, such as regularly arranging antidots to make the (3 n ,3 m ) nanomesh, is proposed to open a sizable bandgap no matter whether the sublattice equivalence keeps or not. In the nanomeshes patterned with the magnetic antidots, the antiferromagnetic coupling adds a quantum parameter to break the sublattice equivalence, resulting in the bandgap opening at the twofold degenerate K (K′) point. Our studies also show that the gap width could be tuned by controlling the antidot density. These results could facilitate the fascinating applications of graphene in the next-generation nanoelectronics. [ABSTRACT FROM AUTHOR]

Abstract: Using first-principles density functional theory and non-equilibrium Greenʼs function formalism for quantum transport calculation, we have investigated the electronic transport properties of the unsymmetrical C121-based molecular junction. Our results show that the current–voltage curve displays a negative differential resistance phenomenon in a certain bias voltage range. The mechanism for the negative differential resistance phenomenon is suggested. The present findings could be helpful for the application of the C121 molecule in the field of single molecular devices or nanometer electronics. [Copyright &y& Elsevier]

Thermal deformation behavior has a significant effect on the microstructure evolution, crystallographic orientation and microhardness of two-phase titanium alloy. In the paper, the evolution rules of microstructure, texture and microhardness of Ti–6.5Al–3.5Mo–1.5Zr–0.3Si (TC11) and Ti–4Mo–4Cr–5Al–2Sn–2Zr (TC17) linear friction welded (LFWed) joint were systematically discussed during the isothermal compression. Comparing with the high microhardness on the welded zone (WZ) after welding, the microhardness value of the whole joint decreases significantly after the pretreatment and isothermal compressions. There is a close relationship between microtexture and plastic deformation. The electron backscattered diffraction (EBSD) analysis method indicates that the distribution of Schmid factor is very uneven, and most of the crystals are aligned to hard orientation on the TC11 WZ; whereas the high Schmid factors occur, and most of the crystals turn to soft orientation on the TC17 WZ, which lead to the plastic deformation of TC17 side more easily than that of TC11 side. With the increasing compression strains, the ratio of low angle grain boundaries (LAGBs) rises, meanwhile, the mean geometrically necessary dislocations (GND) density increases from 2.79 × 1014 m−2 to 4.30 × 1014 m−2, and the fraction of high Schmid factor also goes up slightly. Those can be attributed to the increased deformation energy with the higher compression, which leads to the accumulated driven force and promotes the rotation of grains toward a specific favourable orientation. The relationship between the microhardness and the crystal texture of the TC11/TC17 LFWed joint. [Display omitted] • Rules of microstructure, texture and microhardness of LFWed joint were discussed. • Plastic deformation mechanism of the joint was discussed by the Schmid factors. • The ratio of LAGBs and GND density rises with the increasing compression strains. • Microhardness at the joint is more uniform with the higher isothermal compression. [ABSTRACT FROM AUTHOR]

Selective Laser Melting (SLM) as one of the additive manufacturing technologies can be used to produce Ti–Ni shape memory alloys with complex shape. In this work, equiatomic Ti 50 Ni 50 (at.%) samples were produced by SLM with different scanning speed, and near-fully dense (99.5% relative density) parts were obtained under a low input laser energy density (40 J/mm3) with the scanning speed of 1000 mm/s. The different scanning speeds had limited influence on the phase composition, transformation temperatures and Vickers hardness. Under low magnification, the typical molten pool morphology with inhomogenous microstructure was shown in the samples of SLM-produced Ti–Ni alloy, and self-accommodate martensite (B19') twins with a few austenite (B2), nanoscale Ti 2 Ni and rhombohedral (R) phases were found at higher magnification. Due to the formation of nanoscale Ti 2 Ni phase and inhomogenous microstructure, the SLM-produced Ti–Ni alloy exhbited lower phase transformation temperatures and larger hysteresis temperatures between the start and finish point of the phase transformation compared to the Ti–Ni powder. The formation of the R phase was contributed to the special repeat heating process and stress field formed by Ti 2 Ni phase and dislocations in SLM equiatomic Ti–Ni alloy. The SLM-produced Ti–Ni alloy exhibits higher compressive and tensile fracture strength but lower compressive and tensile fracture strain compared to the conventional cast samples. [ABSTRACT FROM AUTHOR]

Carbohydrate metabolic in muscle of largemouth bass was reprogrammed under hypoxia, and miRNA-124 could regulate lactate transportation by targeting mct1. • Measurements for metabolites parameters in muscle support that metabolic could be reprogrammed during acute hypoxia. • The expression of glycolysis-related genes level in the muscle were significantly upregulated during acute hypoxia. • A dual luciferase reporter assay and qPCR analysis showed that miR-124-5p has a suppressive effect on mct1 expression. • Lactate transportation in the muscle of M. salmoides under hypoxia was evaluated. Carbohydrate metabolism switches from aerobic to anaerobic (glycolysis) to supply energy in response to acute hypoxic stress. Acute hypoxic stress with dissolved oxygen (DO) levels of 1.2 ± 0.1 mg/L for 24 h and 12 h re-oxygenation was used to investigate the response of the anaerobic glycolytic pathway in Micropterus salmoides muscle. The results showed that the glucose concentration was significantly lower in muscle, while the lactic acid and pyruvic acid concentrations tended to increase during hypoxic stress. No significant difference was observed in muscle glycogen, and ATP content fluctuated significantly. The activities of gluconeogenesis-related enzymes were slightly elevated, such as phosphoenolpyruvate carboxykinase (PEPCK). The activities of the glycolytic enzymes increased after the induction of hypoxia, such as hexokinase (HK), pyruvate kinase (PK), and lactate dehydrogenase (LDH). Curiously, phosphofructokinase (PFK) activity was significantly down-regulated within 4 h during hypoxia, although these effects were transient, and most indices returned to control levels after 12 h of re-oxygenation. Upregulated hif-1α , ampkα, hk , glut1 , and ldh mRNA expression suggested that carbohydrate metabolism was reprogrammed under hypoxia. Lactate transport was regulated by miR-124-5p according to quantitative polymerase chain reaction and dual luciferase reporter assays. Our findings provide new insight into the molecular regulatory mechanism of hypoxia in Micropterus salmoides muscle. [ABSTRACT FROM AUTHOR]