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The effects of four different processes, direct quenching + tempering (DQ + T), direct quenching + reheating and quenching + tempering (DQ + RQ + T), forced air cooling + reheating and quenching + tempering (AC + RQ + T), and furnace cooling + reheating and quenching + tempering (FC + RQ + T), on microstructures and precipitates of Mo–Ti microalloyed medium carbon steel were investigated by OM, SEM, TEM, EBSD and mechanical tests. The width of martensite laths (0.22 ± 0.01 μm) produced in DQ + RQ + T was similar to that generated in DQ + T and was narrower than those formed during AC + RQ + T and FC + RQ + T. The effective grain size of the DQ + RQ + T sample was found to be the smallest (0.98 ± 0.38 μm), thus it yielded the finest (Ti, Mo) C precipitates, manifested high strength and excellent plastic toughness, and generated uniform transverse and longitudinal properties. The strength of the DQ + RQ + T sample (longitudinal R m = 1773 MPa) was slightly lower than that of the DQ + T samples and its elongation (A = 11.0%) and impact energy at −40 °C (A kv = 50 J/cm2) were greater than those of the other three samples. Before the RQ process, the DQ cooling process was employed in order to generate large angle grain boundaries to provide more nucleation sites for austenitization. Moreover, the DQ process inhibited the precipitation of Ti during cooling and then formed fine (Ti, Mo) C precipitates during reheating of RQ to prevent austenite grain growth. Therefore, the DQ + RQ + T process generated fully refined austenite grains, made the martensite structure and (Ti, Mo) C precipitates more uniform, and enhanced the effects of fine grain strengthening and precipitation strengthening. In addition, the plasticity and the toughness of the fine and uniform equiaxed grains were also significantly improved, and the formation of acicular cementites was impeded. [ABSTRACT FROM AUTHOR]

The microstructure and hydrogen diffusion behavior of a typical high carbon bainitic steel experienced two different heat treatment history were firstly examined by optical microscope, scanning electron microscope and electrochemical hydrogen permeation test. Hydrogen diffusivity in this investigated steel lies in between those of the pure iron or mild steels and austenitic steels. The underlying mechanism is that although hydrogen diffusion in bainitic ferrite dominated hydrogen transport, percolation effect of the retained austenite as well as its tortuosity effect can significantly decrease hydrogen effective diffusivity and permeability, which was further verified by simplified formulas and models solved by numerical simulation. Hydrogen permeation curve depends on the length of actual hydrogen diffusion paths in ferrite matrix with embedded retained austenite. Image 1 • Hydrogen diffusion in bainites dominants hydrogen transport in ultra-fine bainitic steels. • Diffusion path analysis is an effective way to analyze permeation curves of dual phase steels. • Numerical method is established to deal with hydrogen diffusion in dual-phase steels.. [ABSTRACT FROM AUTHOR]

Influence of a 12 T high magnetic field on the recovery of tempered martensite in the chromium-containing steel was investigated. The results showed that a high magnetic field caused the percentage of low angle boundaries θ between 5° ~ 8° to increase by about 8%, while correspondingly decreased the percentage of high angle boundaries (>15°) by 9%. With the application of the magnetic field, the strain energy increased due to the higher density of free dislocations in the martensite, which leads to the retardation of recovery and little change in its lath shape due to the inhibition of the transition from low to high angle boundaries to maintain lower energy in the matrix. Image 1 • The recovery of martensite was inhibited by high magnetic field. • The percentage of low angle boundaries increased by 12 Tesla magnetic field. • The strain energy increases due to the higher density of free dislocations. • The strain energy inhibited the transition from low to high angle boundaries. [ABSTRACT FROM AUTHOR]

A series of 18Cr–8Ni ASSs with homogeneous or heterogeneous structures were prepared to reveal the unique deformation mechanism of hetero-deformation-induced (HDI) hardening in lamellar heterostructure. By adjusting the annealing temperature, the nano-grained (NG) and coarse-grained (CG) unimodal homogeneous structures were obtained by annealing at 600 °C and 1000 °C, respectively, while the nano-grained/ultrafine-grained (NG/UFG) and ultrafine-grained/fine-grained (UFG/FG) bimodal heterogeneous structures were achieved by annealing at 700 °C and 800 °C. Compared to the conventional bimodal homogeneous structure (UFG/FG), the hetero-zone boundaries (HBs) of bimodal lamellar heterostructure (NG/UFG) can not only provide extra HDI hardening effect, but also coordinate the inhomogeneous deformation for Lüders deformation. The HDI hardening and Lüders deformation greatly facilitate the transformation induced plasticity (TRIP) effect to achieve. This is due to the lower austenite stability in soft region (coarser grain), leading to the formation of deformation-induced martensite (DIM) under lower stress, on the other hand, the Lüders deformation achieved a dynamic balance between both sides of hetero-boundary, avoiding the stress concentration and promoting the TRIP effect. Consequently, the DIM content of the NG/UFG specimen is considerably higher than that of the UFG/FG specimen (78 vol% to 27 vol%). [ABSTRACT FROM AUTHOR]

A 5-cell reversible solid oxide cell stack in external-manifold design is fabricated with planar cells with an active area of 169 cm2, Ni–Y 2 O 3 stabilized ZrO 2 (Ni-YSZ) support, Ni-YSZ functional anode (fuel electrode), YSZ electrolyte, and YSZ-composite cathode (air electrode). It is operated at various temperatures in different atmospheres. In fuel cell mode at 750 °C with H 2 fuel and air oxidant, the stack generates 407 W (481.7 mW cm−2, 81.4 W per cell) at 0.68 A cm−2. In electrolysis mode, with H 2 -55% H 2 O at 750 °C, the current density at the thermo-neutral voltage (6.45 V) is −0.340 A cm−2, and concentration polarization starts at around −0.3 A cm−2. They are −0.592 A cm−2 and above −0.50 A cm−2, respectively, under 80% H 2 O and 800 °C. H 2 production rate increases from 88 NL h−1 to 209 NL h−1, accordingly. Using H 2 -80% H 2 O for fuel electrode at 800 °C, the stack performs at around 7.0 V and −0.5 A cm−2 for up to 900 h without gas leaking and cell delamination and with more severe metal oxidation at the spots where the SUS430 interconnect contacts with Ni foam current collector on the fuel electrode side. [Display omitted] • 5-cell stack generated 407 W with H 2 fuel and air oxidation at 750 °C. • The H 2 production rate was up to 209 NL h−1 at 800 °C and therm-neutral voltage. • The stack operated in SOEC mode for 1000 h without obvious degradation. • No delamination occurred between air electrode and electrolyte. • Unusual oxidation and elements diffusion in interconnect were firstly observed. [ABSTRACT FROM AUTHOR]

The three-dimensional morphology of low-temperature bainite in high-carbon steel was reconstructed by serial sectioning and computer-aided three-dimensional reconstruction techniques. Combined with laser scanning confocal microscope and electron backscatter diffraction analysis, the microstructural evolution and crystallographic orientation of low-temperature bainite were studied. The results show that the three-dimensional morphology of the low-temperature bainite sheaves is a plate-like structure. During the isothermal transformation, some new bainite plates stop growing after impinging on preformed bainite plates. However, some new bainite plates resume growth on the opposite surface of the impingement zone after briefly stopping. This is attributed to the accumulation of strain energy in the collision zone caused by impingement between bainite plates, which provides the driving force for new nucleation, thus stimulating new nucleation on the opposite surface of the collision zone. The bainite formed on the opposite surface maintains the same crystallographic orientation as the "twinned bainite". Finally, the bainite plates form interlocked microstructures in the prior austenite grains via impingement, nucleation, and intersection. • The 3-D morphology of low-temperature bainite is reconstructed. • Impingement between bainite plates stimulates new nucleation. • The same crystallographic orientation is "inherited" in new bainite. [ABSTRACT FROM AUTHOR]

Highlights • The effects of Nb and RE on initial marine corrosion of HSLA steels were compared. • Selective dissolution of the matrix around Al 2 O 3 leads to further propagation of local corrosion. • (Al, RE)-oxy-sulfides prefer to dissolve and a stable pit forms, lowering the local corrosion rate. • RE-bearing steel reveals higher corrosion resistance compared to Nb-bearing steel. • First principle modeling indicates corrosion tendencies: (RE) 2 O 2 S > REAlO 3 > Fe > Al 2 O 3. Abstract In the present paper, the effects of Nb and rare earth elements on initial marine corrosion behavior of low-alloy steels were investigated by first principle modeling as well as multifarious analytical techniques, such as scanning electron microscopy with X-ray microanalysis (SEM/EDS), transmission electron microscopy (TEM), scanning vibrating electrode technique (SVET), and electrochemical workstation. It was found that inclusions played key roles during the corrosion process. Spherified fine (Al, RE)-oxy-sulfide inclusions were formed in RE-bearing steel, which was dissolved preferentially in 0.5 wt% NaCl solution, and inhibited the propagation of initial corrosion. In contrast, coarse Al 2 O 3 inclusions were formed in Nb-bearing steel, thus resulting in the selective dissolution of Fe matrix and further development of initial corrosion. RE-bearing steel demonstrated higher corrosion resistance as compared to Nb-bearing steel. Moreover, the work functions of low-indexed crystallographic planes of the inclusions and the substrate were calculated by first principle modeling, and the findings indicated consistent corrosion tendencies with experimental results, (RE) 2 O 2 S > REAlO 3 > Fe > Al 2 O 3. Finally, a schematic model was proposed to observe the influences of Nb and RE elements on corrosion initiation and propagation behavior of low-alloy steels. [ABSTRACT FROM AUTHOR]

Abstracts The role of long period stacking ordered (LPSO) structure in the corrosion behavior of Mg-Gd-Zn-Zr alloys was investigated by means of potentiodynamic polarization experiments, hydrogen evolution tests, and microstructure characterization. The corrosion rate of the Mg-Gd-Zn-Zr alloys is mainly determined by the acceleration effect of the second phases in the micro-galvanic corrosion. After T4 heat-treatment, the β-(Mg,Zn) 3 Gd eutectic phase in the as-cast Mg-Gd-Zn-Zr alloys transforms into an X phase with a 14H-LPSO structure. According to the results of scanning Kelvin probe force microscopy (SKPFM), the potential difference between LPSO phase and the α-Mg matrix is 243 mV, whereas, it is 290 mV between the eutectic phase and matrix in the as-cast alloys. The low relative potential and volume fraction of the LPSO phase reduce the acceleration degree of micro-galvanic corrosion. As a result, the corrosion resistance of Mg-Gd-Zn-Zr alloys improves significantly by the LPSO structure. Highlights • Corrosion rate of T4 treated alloys with LPSO structure is extremely lower than as-cast alloys without LPSO structure. • Micro-galvanic corrosion dominates the corrosion behavior of Mg-Gd-Zn-Zr alloys. • LPSO phase can improve the corrosion resistance of Mg-Gd-Zn-Zr alloys significantly due to its lower potential. [ABSTRACT FROM AUTHOR]

In the present work, we developed an environmentally protective insulating coating for non-oriented electrical steel, which was composed of phosphate film-forming agent, rare-earth passivating agent, silane coupling agent and polyurethane additive. The morphology, composition, electrochemical properties and corrosion resistance of the coating were characterized by scanning electron microscopy (SEM), confocal Raman microscopy (CRM), scanning vibrating electrode technique (SVET), and electrochemical measurements. The formation mechanism of the coating revealed that the synergistic effect of rare-earth passivating agent and silane coupling agent made the distribution of rare-earth oxides uniform and hindered the agglomeration of phosphate. Further addition of polyurethane formed cross-linked network structures with the original coating to enhance corrosion resistance. The electrochemical results indicated a relatively low corrosion current density (0.12 μA cm−2) and a relatively high polarization resistance (143 kΩ cm2). The SVET results illustrated a good passivation effect of the coating, contributing to a continuous protection to the substrate. In addition, the coating could withstand the annealing test for 2 h and resist the neutral salt spray test for 8 h. Consequently, the comprehensive properties of the coating were found to be higher than industrial standards, satisfying application requirements for non-oriented electrical steel. • An environmentally protective insulating coating for NOES was developed. • Silane coupling agent uniformed rare-earth oxides, hindered phosphate agglomeration. • Polyurethane formed cross-linked network structures with original coating. • The FPCO coating exhibited good corrosion resistance and continuous protection. • Comprehensive properties of the coating were higher than industrial standards. [ABSTRACT FROM AUTHOR]

The precise interaction mechanisms between body-centered cubic Fe and the unavoidable interstitial O atom are critical to understanding oxidation resistance. Even though the Fe–O interaction has been investigated extensively for centuries, the physical evolution processing including the stability, bonding characteristics, and magnetism, remains as one of the most important scientific issues. Here, a four-level (atomic, electronic, orbital, and spin-level) analysis was employed to investigate the precise interactions between Fe and O atoms by multiple complementarity methods (Madelung energy calculation, electronic density analysis, crystal orbital Hamilton population analysis and topology analysis of spin maps). The stability of Fe atoms was enhanced with the O atom at the tetrahedral interstitial site. The bonding strength between Fe and O atoms originates substantially from s orbits. Furthermore, the topology of the minority-spin was changed by the magnetic moment flip of O, and the interaction among Fe atoms were strengthened. A further understanding of the Fe–O mechanism provides a theoretical basis for obtaining excellent physical properties in Fe-based materials. • The bcc-Fe matrix with O at tetrahedral interstitial site is more stable. • The bond strength/system stability originates substantially from the s orbits. • Spin flip of O alters the minority-spin topology, thus enhances the stability of Fe. [ABSTRACT FROM AUTHOR]

The effect of natural aging on the microstructure of carbides and martensite in high chromium cast iron subjected to a destabilizing heat treatment was investigated by correlative experimental and theoretical methods. It was observed for the first time that fine η -(Fe, Cr) 2 C carbides precipitated from the martensite matrix in water-quenched high chromium cast iron during natural room temperature aging, which led to a remarkable hardness increase (by 3.4 HRC). On one hand, the obvious hardness increase was attributed to the fine precipitation of M 2 C carbides which was observed by transmission electron microscopy. On the other hand, it is also caused by high Cr content in the η -(Fe, Cr) 2 C carbides, which was confirmed by first-principles calculations. • The M 2 C carbides are effectively precipitated in high chromium cast iron with natural aging. • The precipitated η -(Fe, Cr) 2 C carbides contribute to a higher hardness of high chrome cast iron at room temperature. • The η -(Fe, Cr) 2 C carbides have a lower formation enthalpy and high theoretical hardness. [ABSTRACT FROM AUTHOR]

In this work, the micro-nano hierarchical porous NiCu catalyst was synthesized by electrochemical dealloying of Zr 70 Ni 15 Cu 15 (at %) metallic glass in 0.05 M hydrofluoric acid (HF) solution at 0.3 V for 1500 s (NPNC-1500). This hierarchical porous structure is characterized by unordered microcracks and nanoporous structure, which consists of uniform metallic nanoparticles and interconnected nanochannels. These nanoparticles, with a diameter size of 50–100 nm, exhibit the even-distributed chemical composition of Ni 10.32 Cu 80.91 O 8.77 (at %). Compared with single nanoporous structure, the micro-nano hierarchical porous catalyst of NPNC-1500 showed much better catalytic activity toward methanol electrocatalytic oxidation in alkaline medium, as well as an excellent electrochemical stability. The enhanced electrocatalysis is mainly attributed to the abundant catalytic active sites and accelerated substance diffusion efficiency, deriving from the perfect micro-nano hierarchical porous structure. These results indicated a favorable application prospect of this cost-effective and high-performance porous catalyst in direct methanol fuel cells. • Micro-nano hierarchical porous NiCu catalyst was prepared by electrochemical dealloying of Zr 70 Ni 15 Cu 15 (at%) metallic glass. • The hierarchical porous NiCu catalyst was consisted of microcracks and nanoporous structure. • This catalyst showed enhanced catalytic activity and stability toward methanol electro-oxidation in alkaline medium. • The enhanced electrocatalytic properties were mainly derived from the micro-nano hierarchical porous structure. [ABSTRACT FROM AUTHOR]

[Display omitted] • The 3d orbit of Fe in triangular prism contributes to the self-magnetic moment. • The magnetic-field-induced Curie temperature shifts to higher temperature. • Magnetic Gibbs free energy reduction resulted in M 7 C 3 precipitation in advance. A combination of first-principles calculations, Weiss molecular field theory and density functional perturbation theory is combined to systematically evaluate the magnetic-field-induced thermodynamic properties of the alloy carbide M 7 C 3 in steel. Special emphasis is focused on the self-magnetic and the external magnetic-field-induced magnetic contribution determined by extending the magnetic heat capacity. The self-magnetism origins from the 3d orbit contribution of the Fe atoms which constituted the carbon-containing trigonal prism. The magnetic-field-induced Curie temperature which triggers the boundary of the long and short-range magnetic order closely related to the Cr content and the magnetic field strengths. The higher external magnetic-field-induced Gibbs energy change provides a potential precipitation strategy in advance for the alloy carbides M 7 C 3 which is well in agreement with the experimental results. Our insights further will extend the mechanistic understanding of magnetic-field-induced phase transformation in ferromagnetic Fe-based alloys, emphasizing the role of external field in minimizing energy and guiding new alloy design. [ABSTRACT FROM AUTHOR]

This study investigates the impact of annealing temperature on the microstructure and mechanical properties of reversion-induced, fine grain strengthened austenitic stainless steels (ASSs). Commercial Cr–Mn–N metastable ASS was cold-rolled at room temperature to a thickness reduction of 60% and then annealed at 700 °C and 1000 °C, respectively. The microstructural evolution of the annealed samples was characterized by optical and transmission electron microscopy (TEM); and by the scanning electron microscopy (SEM) techniques of electron backscatter diffraction (EBSD) and X-ray diffraction (XRD). The results indicated that at 700 °C, reversion of deformation-induced martensite (DIM) to austenite occurred via a combination of diffusion and shear mechanisms, while at 1000 °C, it occurred solely through a shear mechanism. The alterable DIM reversion behavior and controllable recrystallization process resulted in bimodal microstructure in specimens annealed at 700 °C and unimodal microstructure in specimens annealed at 1000 °C. Tensile test results revealed that specimens with a unimodal structure had higher yield strength, while specimens with a bimodal structure had larger elongation for the same average grain size. Comprehensive analysis reveals that the strength-plasticity combination for bimodal specimens was higher than for unimodal specimen. This superior plasticity is related to the formation of more geometrically necessary dislocations (GNDs), deformation twins (DTs), and DIM during tension. • Impact of annealing temperature on the microstructure-properties relationship in reversion-induced Cr-Mn-N ASS was studied.. • Bimodal structure was obtained by the combination of reversion in DR and MSR mechanisms, and recrystallization at 700 °C. • The strength-plasticity combination for the bimodal specimens was higher than unimodal specimens. • The superior plasticity for bimodal specimens is related to the formation of more GNDs, DTs and DIM during tension. [ABSTRACT FROM AUTHOR]

The present study aimed to investigate the impact of pre-deformation on the structure-deformation-property relationship in Cr-Mn-N austenitic stainless steel (ASS). The commercial Cr-Mn-N ASS was cold-rolled (CR) at room temperature with a thickness reduction from 5% to 60%, whose microstructural characteristics were identified by optical microscopy, scanning and transmission electron microscopy, and electron backscatter diffraction together with X-ray diffraction. The results indicated that the microstructure varied from equiaxed austenite in the as-received specimen to the coexistence of stacking faults (SFs), deformation twins (DTs) and strain-induced martensite (SIM) in pre-deformed specimens. Furthermore, detailed TEM results showed that equiaxed dislocation cells, DT nets and dislocation-cell-type α'-M occurred in the 60% CR specimen. Tensile tests revealed that the strength of ASS increased while the plasticity decreased with the increase of pre-reduction deformation. Such mechanical properties were confirmed to be related to the variations in microstructure-dependent deformation mechanisms, varying from planar slip + DTs + SIM in the as-received specimen, to DTs + SIM with 30% reduction, and SIM + minor twinning with 60% reduction, respectively, in the pre-deformed specimens. [Display omitted] • Impact of pre-deformation on the structure-deformation-property relationship in Cr-Mn-N ASS was studied. • Equiaxed austenite varied to coexistence of DT, dislocation cells, lath and dislocation-cell-type α′-M with pre-deformation. • Relationship between grain orientation and microstructural evolution was revealed. • Pre-deformed microstructure variation in Cr-Mn-N ASSs affected deformation mechanisms during tension. [ABSTRACT FROM AUTHOR]

• The framework of M 7 C 3 consists of tetrahedron, octahedron and triangular prism. • Substitution of Cr atoms decreases the magnetic moments of the Fe atoms. • Cr atoms significantly influence the bonding property. • The negative magnetic free energy change results in alloy carbide M 7 C 3 precipitation. Previous experiments have proven that a high magnetic field can make alloy carbide M 7 C 3 (M = Fe, Cr) precipitate ahead of time at intermediate temperatures. First-principles calculations are employed to search the source of magnetic-field-induced alloy carbides precipitation behaviors of orthorhombic M 7 C 3. The basic building units for M 7 C 3 crystals are polyhedrons formed by metal atoms and C atoms. The framework structure of o-M 7 C 3 consists of metal tetrahedrons, metal octahedrons and triangular metal prisms. Magnetic calculations show that the substitution of Cr atoms causes the magnetic moments of the Fe atoms to decrease to different extents. Moreover, Cr atoms also have a magnetic moment antiparallel to the Fe atoms. Electronic structure calculations indicate that the bonds in M 7 C 3 are a mixture of ionic, covalent and metal bonds. The substitution of Cr atoms weakens the ionic and covalent bonds between the Fe and C atoms; however, strengthen the metal bonds between the Fe and Cr atoms. The magnetic free energy change of M 7 C 3 is larger than that of M 2 C and M 3 C at 823 K with a 12 Tesla field, which agrees well with the experimental results for a magnetic field promoting the precipitation of M 7 C 3. This study provides a theoretical basis for the precipitation behaviors induced by magnetic fields in steels. [ABSTRACT FROM AUTHOR]

The objective of this study was to examine the association between the serum copper concentration and the prevalence of diabetes among US adults with hypertension using the data from the National Health and Nutrition Examination Survey (NHANES). The study population was selected from adults aged over 20 years old in the three survey cycles of NHANES from 2011 to 2016. Logistic regression model analyses were applied to determine the independent risky effect of copper to the prevalence of diabetes. Also, a restricted cubic spline (RCS) model was performed to explore the potential nonlinear association between serum copper concentration and the prevalence of diabetes. A total of 1786 subjects (742 cases and 1044 controls) were included, and 924 were men (51.7%), and 742 (41.5%) were diabetic. Compared with non-diabetic individuals, the concentration of serum copper in diabetic patients with hypertension was higher. After adjusting for age, sex, race, education, marital status, body mass index (BMI), family poverty income ratio (PIR), smoking, alcohol drinking, physical activity, systolic blood pressure (SBP), diastolic blood pressure (DBP), and hyperlipidemia, the highest quartile of serum copper concentration significantly increased the risk of diabetes as compared with the lowest quartile (OR: 1.38, 95% CI: 1.01-1.92, p trend  = 0.036). The results of RCS analysis showed significant non-linear relationship between serum copper concentration and prevalence of diabetes (p-non-linear = 0.010). This study finds that serum copper concentration are significantly associated with risk of diabetes in hypertensive patients, which suggests copper as an important risk factor of diabetes development., (© 2024 The Authors. Journal of Cellular and Molecular Medicine published by Foundation for Cellular and Molecular Medicine and John Wiley & Sons Ltd.)

The deposition time was controlled to prepare Mn nanowires of different lengths and diameters on templates of anodic aluminum oxide (AAO) with different pore sizes. The surface of as-prepared Mn nanowires was modified with SiO 2 using the sol-gel method to improve their dispersion in aqueous solution. The effects of the diameter and length of the as-prepared Mn nanowires coated with SiO 2 on the relaxivity were investigated. It was found that the Mn@SiO 2 nanowires have smaller diameters and a higher longitudinal relaxivity ( r 1 ) with an increased length. Mn3@SiO 2 nanowires had the highest r 1 value of 5.8 mM -1 s -1 among the Mn@SiO 2 nanowires (Mn3 nanowires have a diameter of about 30 nm and a length of about 0.5 μm length). Additionally, the biocompatibility and in vivo imaging ability of the Mn3@SiO 2 nanowires were evaluated. The Mn3@SiO 2 nanowires had good cytotoxicity and biocompatibility, and the kidney of SD rats showed a positive enhancement effect during small animal imaging at 1.5 T. This study showed that the Mn3@SiO 2 nanowires could potentially become contrast agents (CAs) of longitudinal relaxation time ( T 1 ).

A facile template method was employed to synthesize Fe nanowires of different sizes, dimensions. Comprehensive analyses were conducted to explore their morphology, structure, composition, and magnetic properties. The surface of as-prepared Fe nanowires was modified with SiO 2 by sol-gel method to improve the dispersion of as-prepared Fe nanowires in aqueous solution. Furthermore, the relaxation properties, biocompatibility and in vivo imaging abilities of the Fe@SiO 2 nanowires were evaluated. The study revealed that the SiO 2 -coated Fe nanowires functioned effectively as transverse relaxation time (T 2 ) contrast agents (CAs). Notably, as the length of the Fe@SiO 2 nanowires increased, their diameter decreased, leading to a higher the transverse relaxivity (r 2 ) value. Our study identified that among the Fe nanowires synthesized, the Fe3@SiO 2 nanowires, characterized by a diameter of around 30 nm and a length of approximately 500 nm, exhibited the highest r 2 value of 59.3 mM -1  s -1 . These nanowires demonstrated good biocompatibility and non-toxicity. Notably, upon conducting small animal imaging a 1.5 T with Sprague-Dawley rats, we observed a discernible negative enhancement effect in the liver. These findings indicate the promising potential of Fe@SiO 2 nanowires as T 2 CAs, with the possibility of tuning their size for optimized results., (© 2023. The Author(s).)

Objectives: This study aimed to investigate the hypoglycemic effect of highland barley β-glucan (HBG) on mice with type 2 diabetes (T2D), and determine whether the hypoglycemic effects are related to modulations of the gut microbiota., Methods: T2D was induced with a high-fat diet and streptozotocin in the mice. HBG was orally administered to mice with T2D for 4 wk, and biochemical indices were analyzed in the serum and liver. Fecal samples were collected and analyzed with high-throughput 16S ribosomal RNA sequencing., Results: Intake of HBG for 4 wk suppressed the body weight, as well as liver and heart indices, and regulated the levels of fasting blood glucose, serum insulin, blood lipid, oxidative damage, and inflammatory reaction in mice with T2D. Furthermore, HBG reversed the gut microbiota dysbiosis in mice with T2D by increasing the abundance of Lachnospiraceae_UCG-006, Streptococcaceae, and Eggerthellaceae, and by decreasing the abundance of Parasutterella., Conclusions: Our findings indicate that the antidiabetic abilities of HBG might be related to the improvement of gut microbiota imbalance., (Copyright © 2022. Published by Elsevier Inc.)

Gastric cancer (GC) ranks fifth in global cancer diagnosis and fourth in cancer-related death. Despite tremendous progress in diagnosis and therapeutic strategies and significant improvements in patient survival, the low malignancy stage is relatively asymptomatic and many GC cases are diagnosed at advanced stages, which leads to unsatisfactory prognosis and high recurrence rates. With the recent advances in genome analysis, biomarkers have been identified that have clinical importance for GC diagnosis, treatment, and prognosis. Modern molecular classifications have uncovered the vital roles that signaling pathways, including EGFR/HER2, p53, PI3K, immune checkpoint pathways, and cell adhesion signaling molecules, play in GC tumorigenesis, progression, metastasis, and therapeutic responsiveness. These biomarkers and molecular classifications open the way for more precise diagnoses and treatments for GC patients. Nevertheless, the relative significance, temporal activation, interaction with GC risk factors, and crosstalk between these signaling pathways in GC are not well understood. Here, we review the regulatory roles of signaling pathways in GC potential biomarkers, and therapeutic targets with an emphasis on recent discoveries. Current therapies, including signaling-based and immunotherapies exploited in the past decade, and the development of treatment for GC, particularly the challenges in developing precision medications, are discussed. These advances provide a direction for the integration of clinical, molecular, and genomic profiles to improve GC diagnosis and treatments., (© 2022. The Author(s).)

First-principles calculations are used to study the structure, magnetism and mechanical anisotropy properties of M 6 C (M = Fe, Mo) carbides. The stability of alloy carbide M 6 C can be improved when Mo atoms occupy the 48f Wyckoff position. Fe 3 Mo 3 C with Mo atoms occupying 48f position and Fe atoms occupying 16d and 32e positions has the best structural stability. The magnetic moment is triggered when the Fe content is approximately 0.5, suggesting that there exists a critical value between the paramagnetic nature and ferromagnetism. Carbides with Fe content above 0.5 have stronger magnetism. Higher Fe content corresponds to the stronger chemical bonding of carbides, resulting in improved elastic properties when Mo atoms are held in 48f position. The special carbides Fe 4 Mo 2 C and Fe 3 Mo 3 C (Fe at 48f site, Mo at 16d and 32e sites) correspond to the excellent mechanical properties. These results are helpful in providing a theoretical foundation of the possible direction for the advances of the excellent physical properties in Mo-containing steel., (© 2022 IOP Publishing Ltd.)

Background and Aims: Gut microbiota and their metabolic products might play important roles in regulating the pathogenesis of choledocholithiasis concurrent with cholangitis (CC). The aim of this study was to explore the characteristic gut dysbiosis, metabolite profiles and the possible roles in patients with CC., Methods: A case-control study was carried out to analyze the alterations in the intestinal microbiota and their metabolites in patients with CC (n = 25) compared with healthy controls (HCs) (n = 25) by metagenomic sequencing to define the gut microbiota community and liquid chromatography/mass spectrometry (LC/MS) analysis to characterize the metabolite profiles., Results: Significantly reduced Shannon diversity index (p = 0.043) and differential overall fecal microbiota community in CCs were observed. Twelve dominant altered species were identified and analyzed (LDA score > 3.0, p < 0.05) (Q value < 0.05), including unclassified&#95;f&#95;Enterobacteriaceae, Escherichia&#95;coli, Roseburia&#95;faecis and Eubacterium rectale. Moreover, the levels of KEGG pathways related to biofilm formation of Escherichia coli, lipopolysaccharide (LPS) biosynthesis, and the metabolism of propanoate and glutathione in CCs were significantly altered. Finally, 47 markedly changed metabolites (VIP > 1.0 and p < 0.05), including low level of kynurenic acid (KYNA) and high concentration of N-palmitoylsphingosine involving tryptophan metabolism and sphingolipid signaling pathways, were identified to validate aberrant metabolic patterns in CCs, and multiple correlated metabolic modules involving bile inflammation were altered in CCs., Conclusion: Our study provides novel insights into compositional and functional alterations in the gut microbiome and metabolite profiles in CC and the underlying mechanisms between gut microbiota and bile inflammation., (© 2021. Asian Pacific Association for the Study of the Liver.)

The catalyst of nanoporous Cu (NP-Cu) powders, with the chemical composition of Cu 79.63 Ni 6.85 O 13.53 (at%), was successfully fabricated by dealloying of Zr-Cu-Ni-Al metallic glassy precursors. The as-prepared NP-Cu powders, co-existing with Cu 2 O phase on Cu ligament surface, had a three-dimensional network porous structure. The NP-Cu powders/H 2 O 2 system showed superior catalytic degradation efficiency toward azo dyes in both acidic (pH 2) and neutral (pH 7) environments. Moreover, the cyclic tests indicated that this powder catalyst also exhibited good durability. A novel degradation mechanism of NP-Cu powders/H 2 O 2 was proposed: the high degradation performance in acidic environment was mainly derived from heterogeneous reaction involved with a specific pathway related to Cu 3+ to produce HO·, while in neutral environment it was primarily resulted from homogeneous reaction with the generation of HO· from the classical Cu-based Fenton-like process. This work indicates that the NP-Cu powders have great potential applications as catalysts for wastewater treatments., (© 2022 IOP Publishing Ltd.)

To overcome the negative contrast limitations, and to improve the sensitivity of the magnetic resonance signals, the mesoporous silica coated Fe/Mn multilayered nanowires (NWs) were used as a T 1 -T 2 dual-mode contrast agents (CAs). The single component Fe and Mn NWs, and Fe/Mn multilayer NWs were synthesized by electrodeposition in the homemade anodic aluminum oxide (AAO) templates with the aperture of about 30 nm. The structural characterization and morphology of single component and multisegmented NWs was done by X-ray diffraction and transmission electron microscopy. The elemental composition of Fe/Mn multilayerd NWs was confirmed by energy-dispersive X-ray and energy-dispersive spectrometer. Vibrating sample magnetometer was used to test the magnetic properties, and 1.5 T magnetic resonance imaging (MRI) scanner was used to measure the relaxation efficiency. Importantly, the MRI study indicated that the Fe/Mn multilayer NWs showed a significant T 1 -T 2 imaging effect, and have longitudinal relaxivity (r 1 ) value, that is, 1.25 ± 0.0329 × 10 -4 μM -1 s -1 and transverse relaxivity (r 2 ), that is, 5.13 ± 0.123 × 10 -4 μM -1 s -1 , which was two times of r 1 value (0.654 ± 0.00899 × 10 -4 μM -1 s -1 ) of Mn NWs, and r 2 value (2.96 ± 0.0415 × 10 -4 μM -1 s -1 ) of Fe NWs. Hence, Fe/Mn multilayer NWs have potential to be used as T 1 -T 2 dual-mode CAs., (© 2020 Wiley Periodicals LLC.)

Background: To investigate the dynamic changes in high-resolution computed tomography (HRCT) findings of coronavirus disease 2019 (COVID-19) patients with different severities in different disease stages., Methods: We retrospectively collected the clinical and imaging data of 96 patients in Yunnan Province, China, who were diagnosed with COVID-19 between January 22 and March 15, 2020. Based on disease severity, the COVID-19 patients were classified into four types: mild (n=15), moderate (n=59), severe (n=19), and critical (n=3). Based on hospital stay and number of computed tomography (CT) scans, the clinical/disease course was divided into four stages, including stage 1 (days 0-4), stage 2 (days 5-9), stage 3 (days 10-14), and stage 4 (days 15-19). The HRCT findings, CT value, and lesion volume were analyzed for each stage and compared among the four stages of COVID-19 patients., Results: CT findings were negative over the four stages for all mild COVID-19 patients. More lesions were found in the peripheral lung fields than in peripheral + central fields (P<0.05), and the number of negative patients in stage 4 were more than those in stages 1-3 (P<0.05). The left and right lower lobe were the most frequently affected lobes (P<0.05). In moderate patients, round ground glass opacities (GGOs) decreased from stage 1 to stage 4; partial consolidation peaked in stage 2 and then decreased in stages 3-4; fibrous stripes and subpleural lines increased from stage 1 and peaked in stage 4. Partial consolidation and consolidation were more common in severe patients than in moderate patients over the disease course (P<0.05). Critical patients showed significant partial consolidation and consolidation; The CT value, lesion volume and lesion volume percentage significantly decreased from stages 1-2 to stage 4 (all P<0.05)., Conclusions: The dynamic changes in lung HRCT images are clinically related to the disease course of COVID-19.

Tongue squamous cell carcinoma (TSCC) is the most common cancers of oral, owing to the high invasive and metastatic ability, patients with TSCC have poor prognosis, it's important to explore the regulatory mechanism of TSCC invasion and metastasis. Previous studies suggest OSR1 suppresses the progression of gastric cancer and renal cell carcinoma, but its role in TSCC hasn't been studied. Here, we found OSR1 was downregulated in TSCC cells and specimens, Transwell and 3D spheroid invasion assay suggested OSR1 overexpression inhibited TSCC cell migration and invasion, while its knockdown promoted TSCC cell migration and invasion. Mechanism analysis found OSR1 expression was negatively correlated with NF-κB pathway and its targets. Western blot and NF-κB activity analysis suggested OSR1 inhibited NF-κB activity. Double inhibition of OSR1 and NF-κB significantly inhibited TSCC cell migration and invasion. These findings suggested OSR1 inhibited TSCC cell migration and invasion through inhibiting NF-κB pathway., (Copyright © 2018. Published by Elsevier B.V.)

Objective: To screen the microRNAs involved in colon cancer proliferation and to investigate the expression and regulating function of target miRNA in colon cancer., Methods: Mitochondrial transcription factor A(TFAM), which was proved to be an oncogene to colon cancer in prior study, was used as target gene. The microRNAs involved in colon cancer proliferation were screened with miRWalk 2.0 software. The expression of screened miRNAs was examined in 30 samples of colon cancer tissue, para-cancer tissue, normal colon cell strain, and 3 colon cancer strains (SW480, HT-29, and HCT116) by real-time PCR. MiR-204 presenting lowest expression was selected to further study in SW480 cells. Dual luciferase reporter assays was performed to examine the association of TFAM with miR-204. Anti-miR-204 lentivirus and miR-240 lentivirus were used to down-regulate and up-regulate miR-204 expression respectively. Change of TFAM protein expression in SW480 cells was detected by Western blotting, and change of SW480 cells proliferation was detected by MTT and BrdU assay after lentivirus transfection., Results: After screening, the candidate miRNAs were miR-204, miR-211, miR-214, miR-381 and miR-590-3p. Expressions of miR-204, miR-211, miR-214 and miR-381 were lower, but miR-590-3p expression was higher, in colon cancer tissues than those in para-cancer tissues(all P<0.05). Meanwhile expressions of above 4 miRNAs(miR-204, miR-211, miR-214 and miR-381) were also lower, but miR-590-3p expression was higher as well, in SW480, HT-29 and HCT116 cells compared to normal colon cells(all P<0.05). Among above 4 miRNAs, miR-204 showed the lowest expression in both colon cancer tissues and cell lines. Expression of miR-204 was negatively correlated with TFAM expression in colon cancer tissues(P<0.05). Dual luciferase reporter assays revealed TFAM could be integrated with miR-204 directly, suggesting TFAM as the direct target of miR-204. After up-regulating miR-204 by lentivirus, expression of TFAM decreased and proliferation increased in SW480 cells(all P<0.05). After down-regulating miR-204 by lentivirus, expression of TFAM increased and proliferation decreased in SW480 cells(all P<0.05)., Conclusion: MiR-204 inhibits TFAM expression and up-regulates the proliferation of colon cancer cells SW480.

Background: Our aim was to establish a new pN staging system for gastric cancer based on the number and location of metastatic lymph nodes (MLNs) and to compare it with other systems., Methods: We retrospectively analyzed the prognostic data of 521 gastric cancer patients who underwent curative resection. Survival analyses were used to establish a pN staging system that considers both the number and location of MLNs and to compare discriminatory ability and monotonicity of gradients (linear trend χ (2) score), homogeneity ability (likelihood ratio test), and prognostic stratification ability (Akaike information criterion) between Japanese Gastric Cancer Association (JGCA) and Union for International Cancer Control (UICC) systems., Results: Cut-point survival analysis divided pN(+) patients into two groups: Nxn1~6 and Nxn≥7. N0, N1, N2, and N3 (the previous classifications) were replaced by N0, N1n1~6, N2n1~6, and N1n≥7 + N2n≥7 + N3n1~6 + N3n≥7, respectively. Compared with two widely used staging systems, the new system had the highest likelihood ratio test [106.06 (new) vs 95.09 (JGCA) vs 94.33 (UICC)] and linear trend χ (2) scores [102.30 (new) vs 89.12 (JGCA) vs 86.97(UICC)] and the lowest Akaike information criterion (AIC) score [2,283.88 (new) vs 2,285.31 (JGCA) vs 2,299.88 (UICC)]., Conclusion: A new pN staging system based on the number and location of MLNs is an efficient prognostic indicator of the survival of patients with gastric cancer following radical surgery.