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Myeloid cells are known to play a crucial role in creating a tumor-promoting and immune suppressive microenvironment. Our previous study demonstrated that primary human monocytes can be polarized into immunosuppressive myeloid-derived suppressor cells (MDSCs) by cancer-associated fibroblasts (CAFs) in a 3D co-culture system. However, the molecular mechanisms underlying the immunosuppressive function of MDSCs, especially CAF-induced MDSCs, remain poorly understood. Using mass spectrometry-based proteomics, we compared cell surface protein changes among monocytes, in vitro differentiated CAF-induced MDSCs, M1/M2 macrophages, and dendritic cells, and identified an extracellular vesicle (EV)-mediated secretory phenotype of MDSCs. Functional assays using an MDSC/T-cell co-culture system revealed that blocking EV generation in CAF-induced MDSCs reversed their ability to suppress T-cell proliferation, while EVs isolated from CAF-induced MDSCs directly inhibited T-cell function. Furthermore, we identified fructose bisphosphatase 1 (FBP1) as a cargo protein that is highly enriched in EVs isolated from CAF-induced MDSCs, and pharmacological inhibition of FBP1 partially reversed the suppressive phenotype of MDSCs. Our findings provide valuable insights into the cell surface proteome of different monocyte-derived myeloid subsets and uncover a novel mechanism underlying the interplay between CAFs and myeloid cells in shaping a tumor-permissive microenvironment.

Twins play a crucial role in elucidating the structure and deformation characteristics of materials. However, in materials with low-symmetry crystal structures, solving the twin relationships remains a challenging task. In this study, we propose a general method for determining twin elements K1, η1, K2, and η2, which are essential for twin analysis. The proposed method involves three main steps: (1) representing misorientation data measured by electron back-scattered diffraction (EBSD) and transmission electron microscopy (TEM) in matrix form, (2) identifying additional 180° rotation elements related to twin elements K1 or η1 by traversing all symmetrically equivalent misorientations, and (3) using a minimum and crystal structure-dependent uniform shear as the constraint to determine the other twin elements (K2andη2). By combining the experimental data and the proposed method, we systematically analyze the complex twin relationships of Cu–Zn–Al shape memory alloys (SMAs) with monoclinic martensite (M18R). This methodology has been demonstrated to be effective and possesses broad applicability.

Cu–Al2O3–TiB2 is an important high-performance dual-phase dispersion strengthened copper alloy. The problem of serious coarseness and agglomeration of TiB2 and Al2O3 particles is a bottleneck that restricts the preparation of high-performance Cu–Al2O3–TiB2 alloys by traditional liquid-phase in-situ reaction method. In this paper, an idea of combining the split cavity melting of complex reactants and efficient solidification of melt was proposed, and a new liquid phase in-situ reaction technology for dual-phase strengthened metal matrix composites was invented. Compared with the traditional liquid phase in-situ reaction method, the strengthening particles in the Cu-0.75Al2O3-0.75TiB2 (wt.%, nominal composition) prepared by the new liquid phase in-situ reaction technology were more uniform, and the tensile strength and hardness were significantly improved. Large-deformation cold rolling can improve distribution of particles. With the increase of deformation, the main deformation mode of the composite changed from matrix plastic deformation to matrix-particle shear deformation, with the main fracture mechanism changing from particle-matrix interface fracture to particle shear fracture. The new liquid phase in-situ reaction technology effectively solved the problem of particle coarsening and agglomeration in Cu–Al2O3–TiB2 composites. The new liquid phase in-situ reaction technology combined with large deformation is a new process with high efficiency and short flow for preparing dual-phase dispersion strengthened copper alloys.

In this study, the effects of differences in grain size, grain boundary type and misorientation on the initiation of discontinuous precipitates are investigated for the Cu–5Ni–1.25Si alloy. Samples with different grain sizes are obtained by thermomechanical treatment, and the smaller the grain size, the higher the percentage of discontinuous precipitate at the same aging time, while there is no significant difference in the growth rate of the reaction front of discontinuous precipitates. EBSD is used to study the effect of grain boundary misorientation on discontinuous precipitates, the characteristics of discontinuous precipitates initiation on different grain boundaries are investigated by multivariate statistical analysis. It is found that discontinuous precipitates only initiate from random grain boundaries instead of coincident site lattice boundaries, where random grain boundaries with misorientation angles of 30–50° are more prone to discontinuous precipitates. And the initiation of DPs at different misorientation axes is different. There is a clear borderline for the axes such as , , and . The grain boundaries below this borderline do not initiate DP, while all grain boundaries below this angle initiate DPs. The cases for axes such as , , and are more complicated. On these misorientation axes, grain boundaries with lower or higher misorientation angles do not initiate DPs, while grain boundaries at intermediate range misorientation angles do initiate DPs.

The Cu–Ni–Sn–Ti–Cr and Cu–Ni–Sn–Ti–Cr–Ce alloys were compressed at 500–900 °C with 0.001–10 s−1 strain rates using the Gleeble 1500 deformation simulator. The effects of Ce addition on the microstructure and recrystallized grains of Cu–Ni–Sn–Ti–Cr alloy were investigated using EBSD and TEM. A constitutive equation was established to calculate the activation energy for the alloy hot deformation, and the optimal processing parameters were obtained. The corresponding texture of the Cu–Ni–Sn–Ti–Cr–Ce alloy deformed at 800 °C with 0.01 s−1, 0.1 s−1 and 1 s−1 strain rates is the {112} Copper, {001} Cubic and {011} Goss texture. The texture of the Cu–Ni–Sn–Ti–Cr alloy deformed at 800 °C and 0.1 s−1 strain rate is the {011} Goss texture. The strain rate and Ce addition can change the alloy texture. The precipitation phase in Cu–Ni–Sn–Ti–Cr (-Ce) alloy is mainly CuNi2Ti phase, and the addition of Ce can promote the precipitation of fine nanoscale precipitation phase in the alloy. Moreover, the addition of Ce can promote the dynamic recrystallization of the alloy, but the dynamic recrystallization of the alloy is suppressed with the increase of the hot deformation rate at the heat deformation temperature of 800 °C.

The aim of this study is to observe the organization and properties of Al2O3–Cu/WSiC–Y2O3 composites and to investigate the effect of Y2O3 incorporation on the electrical contact properties of the composites. Preparation of Al2O3–Cu/30W3SiC(0.5Y2O3) composites by rapid hot-pressing sintering technique. The conductivity of the composites is 59.3 %IACS and 58.3 %IACS, respectively. Hardness is 179 HV and 183 HV, respectively. Thermal conductivity is 108 W/(m·k) and 275 W/(m·k), respectively. The dense structure of the composites and the homogeneous distribution of reinforcing phases give the composites excellent overall performance. The addition of Y2O3 increases the resistance of the materials to arc erosion. The amount of material transfer and loss is significantly reduced, and the arc ablation phenomenon is reduced. The arc duration was significantly reduced from 4.48 ms to 0.44 ms, 5.72 ms–4.68 ms, 6.23 ms–5.52 ms, and 12.5 ms–8.59 ms, respectively; and the melt force was significantly reduced to 58.9%, 81.4%, 87.5%, and 89.4% of the original.

Cupronickel alloys have a variety of applications in marine engineering due to their good mechanical and corrosion properties. In this work, the effect of Cr on the corrosion behavior of Cu–10Ni–1.6Fe–0.5Mn alloy in 3.5 wt% NaCl solution was investigated through electrochemical and surface characterization. The results indicate that Cu–10Ni–1.6Fe–0.5Mn–0.3Cr alloy has better corrosion resistance performance compared to Cu–10Ni–1.6Fe–0.5Mn alloy in NaCl solution. The addition of Cr reduces the corrosion current density of cupronickel alloys from 7.82 μA/cm2 to 7.10 μA/cm2. The better corrosion resistance performance of the Cu–10Ni–1.6Fe–0.5Mn–0.3Cr alloy could be mainly attributed to the incorporation of Cr3+ ions in Cu2O lattice during corrosion. The corrosion product film of Cu–10Ni–1.6Fe–0.5Mn–0.3Cr alloy mainly contains the compounds including Cu2O, NiO, γ-FeOOH, Cr2O3, and Cu2(OH)3Cl. The formation of Cr2O3 can further enhance the stability of corrosion film and improve the corrosion properties of the alloy.

60NiTi alloy is an important biomedical, structural and functional material. In this paper, the effects of heat treatment (temperature, time and cooling rate) on the microstructure and properties of 60NiTi alloy were studied, and the softening and hardening mechanisms were revealed. The results showed that the number of Ni4Ti3 phase enhanced with an increase of the cooling rate and the precipitation of Ni3Ti phase was inhibited after annealing at 950∼1075 °C followed by water-cooling. The orientation relationship between NiTi matrix and Ni4Ti3 phase obey the rule: [111]NiTi//[0001]Ni4Ti3 and (123¯)NiTi//(112¯0)Ni4Ti3. The faster the cooling rate was, the higher the hardness of the alloy was. The hardness of alloy under different cooling rate ranked from high to low was water-cooling, oil-cooling, liquid nitrogen-cooling, air-cooling and furnace-cooling. The hardness of the 60NiTi alloy was 316 HV after annealing at 1075 °C for 4 h followed by furnace-cooling, and the hardness sharply increased to 669 HV after annealing at 1075 °C for 4 h followed by water-cooling. The phase transformation of Ni4Ti3→Ni3Ti during cooling mainly contributed to the hardness decrease of the 60NiTi alloy.

Improving high-temperature strength and resistance to high-temperature softening is an important method to promote the application of high-performance Cu-Cr-Zr alloy in fields such as resistance welding electrodes and high-speed railway contact wires. A Cu-1.0Cr-0.4Zn-0.1Zr-0.05Si alloy was designed and the combining effects of Zn and Si elements on the microstructure and high-temperature mechanical properties of the alloy were studied. The tensile strength of the alloy at room temperature was 556 MPa, and it was 349 MPa at 500℃ with a softening temperature of 620℃. The main strengthening phases of the alloy were submicron Cr3Si and nano-scaled Cr-rich precipitates. The Zn elements were uniformly solid-solved in the Cu matrix, and the addition of Zn and Si elements significantly retarded the phase transformation of the Cr-rich precipitates. Thermodynamics and kinetics analysis showed that Zn and Si elements promoted the dispersive precipitation of the nano-scaled FCC coherent Cr-rich precipitates by reducing the nucleation energy barrier, while the Si and Zr elements inhibited the coarsening of the Cr-rich precipitates by enriching at the phase boundaries, effectively impeding dislocation motion and grain boundary migration, which mainly contributed to good high-temperature strength and resistance to softening of the Cu-Cr-Zn-Zr-Si alloy.

With China entering the era of high-quality development, it is of vital importance to improve strategic decision quality (SDQ) of state-owned enterprises (SOEs). As one of the most basic strategic decisions in the process of SOEs reform, position evaluation (PE) is seldom studied from the perspective of strategic decision. Instead of adopting the single decision-making body of traditional SDQ evaluation, a new PE model based on the multi-level strategic decision-making body and aiming at the dynamic balance between strategic stability and strategic change is constructed under the WSC (i.e., “Who”-“Should do”-“Can do”) framework combining top-down strategy and bottom-up strategy. Compared with the traditional model, the three key phases of this new PE model are establishing decision-making body, determining weight of bodies, and optimizing subject weights by K-means. The empirical results show that the model can comprehensively consider the opinions of senior, middle and grass-roots employees by reasonably optimizing subject weights, so as to effectively optimize the existing PE in SDQ of SOEs. This provides a direction for the SDQ optimization of SOEs and a new idea for SDQ evaluation research.

In the present work, the Cu-1.35Ni-1Co-0.55Si alloy with multiple twins and ultra-low interfacial mismatch precipitates was obtained by liquid nitrogen dynamic plastic deformation (DPD) and aging treatment. It has abnormally high work hardening ability, which is more than twice that of the previous DPD treatment without aging. In addition, it has excellent comprehensive properties, and its strength, electrical conductivity, and elongation are 816.4 MPa, 40.2% IACS and 11.3% respectively. The fine multiple twins do not coarsen significantly during peak aging, and the dispersed nano precipitates (∼3 nm) further enhance the strength of the Cu-Ni-Co-Si alloy. In addition, the low interfacial mismatch strain between the precipitates and the matrix also ensures adequate elongation. The Cu-Ni-Co-Si alloy has high strength, electrical conductivity, and ductility under the simultaneous action of various mechanisms (grain boundary strengthening, precipitation strengthening, dislocation strengthening and stacking faults). This strategy paves a new avenue for developing precipitation-strengthened alloys with excellent comprehensive properties.

The effect of graphene on the thermal deformation of Cu/CeO2/Cr and GO-Cu/CeO2/Cr composites was studied. The isothermal compression test was carried out with Gleeble-1500D thermomechanical simulation device in the range of 600–900 °C and strain rate of 0.001–1 s−1. The microstructure after deformation was characterized and analyzed by optical microscope, scanning electron microscope (SEM), transmission electron microscope (TEM) and electron backscatter diffraction (EBSD). The interaction of work hardening, dynamic recovery and dynamic recrystallization was described. The constitutive equation was successfully established. The results show that Cr particles are extruded into strips, and nano CeO2 particles nail dislocations, which inhibit dynamic recovery and dynamic recrystallization. Dispersion strengthening, twin strengthening and grain refinement strengthening occur the thermal deformation of GO-Cu/CeO2/Cr composites, increase the flow stress and activation energy of the composites, and inhibit the dynamic recrystallization of the composites. When the hot deformation temperature increases, the texture orientation is strengthened. GO-Cu/CeO2/Cr composites have typical dynamic recovery characteristics and high temperature properties.

A borocarburized layer was successfully fabricated on the surface of Q235 low-carbon steel via double glow treatment to improve the wear resistance at elevated temperature. The phase composition and microstructure of borocarburized layer were investigated by XRD and SEM. The microhardness of borocarburized layer from the surface to the substrate were detected. And the tribological behaviors of borocarburized layer and substrate were investigated under the dry-sliding against ZrO2 ball at three temperatures. The results indicate that the borocarburized layer consists of an outermost boride layer and a transition layer of carburized layer. The boride layer with main phase of Fe2B has a high hardness around 1700 HV, and the hardness of transition layer with main phase of Fe5C3 is around 600 HV. The novel gradient structure of an outermost boride layer and inner carburized layer is design in this research decreases the hardness mismatch of coating to prevent the boride layer peeling off. The friction coefficient and specific wear rate of borocarburized layer are much lower than that of substrate at the same temperature. In addition, the wear mechanism of substrate is mainly fatigue wear and slightly adhesive wear at 20℃. When the wear test performs at 200℃, the substrate wear mechanism is adhesive wear and fatigue wear. The wear mechanism of borocarburized layer is main abrasive wear at 20℃ and 200℃. And the wear mechanism of both substrate and borocarburized layer are main oxidation wear and adhesive wear at 500℃. The borocarburized layer effectively improves the wear resistance of low carbon steel due to the higher hardness and great thermal stability at high temperature.

Copper alloys are widely used in the lead frame, high-speed railway and other applications due to their high electrical conductivity and adequate mechanical properties. In this work, the texture and microstructure evolution under hot deformation of Cu-Ni-Si, Cu-Co-Si and Cu-Fe-P alloys were investigated. In order to analyze the texture evolution, the standard pole figures and ODF figures were established. The TEM analysis shows that the addition of trace elements promoted the dispersion of nanoscale precipitated phase particles in the matrix, which can hinder the movement of grain boundaries and dislocations. In addition, the suitable hot processing parameters for the Cu-Fe-P alloy were determined from the hot working diagram. Finally, the comprehensive diagrams for the effects of addition of the alloying elements on the electrical conductivity and ultimate tensile strength of the Cu-Ni-Si and Cu-Fe-P alloys were obtained.

The evolution and strengthening effect of nanoscale precipitates of the aged Cu-Mg-Fe-Sn-P-Y alloy were investigated via aging treatment in the 400–480 °C temperature range and the 10–480 min aging time range. Nanoscale γ-Fe particles uniformly distributed in the matrix caused dispersion strengthening in the peak-aging stage and transformed to α-Fe at the over-aging stage. The Mg3P2 secondary phase hindered the appearance of coarse Fe3P and formed definite orientation relationship (OR) of cubic to cubic with the Cu matrix after 480 min aging, Cu||Mg3P2, (002)Cu||(008)Mg3P2. The optimal aging parameter for the Cu-Mg-Fe-Sn-P-Y alloy is 60% cold deformation and aged at 460 °C for 20 min. The corresponding tensile strength is 599 MPa with the conductivity of 71.1%IACS and the elongation of 6.9%. Compared with the current contact wire, the ultimate tensile strength and conductivity of the studied alloy increased by 20% and 15%, respectively.

Coarse particles in Cu-0.39Cr-0.24Zr-0.12Ni-0.027Si alloy were studied with scanning electron microscopy and transmission electron microscopy. Three types of coarse particles were determined: a needle-like Cu5Zr intermetallic phase, a nearly spherical Cr9.1Si0.9 intermetallic phase and (Cu, Cr, Zr, Ni, Si)-rich lath complex particles. The crystallographic orientation relationships of the needle-like and nearly spherical coarse particles were also determined. The reasons for formation and the role of the coarse phases in Cu-Cr-Zr alloys are discussed, and some suggestions are proposed to control the coarse phases in the alloys.

Due to severe cracking tendency in IC10 single crystal Ni3Al-base alloy jointed by electron beam welding, the solidification crack in the IC10 alloy weldment is detrimental for crucial applications in industry. In this paper, the cracking mechanism in the IC10 alloy joint was investigated, and a perfect joint without any crack is obtained by controlling chemical composition in weld, which microhardness is equivalent to the IC10 alloy and tensile strength is up to 900 MPa reaching 1.5 times of the IC10 alloy. The cracking initiation is derived from the liquid film of low melting point precipitated phase-Ta2C along grain boundary under welding stress during solidification. With chemical composition controlling that a 0.4 mm Inconel718 alloy layer is deposited by electron beam freeform fabrication on the welding path before welding, the finer high melting point NbC phases replacing Ta2C phases is precipitated along grain boundary, and the preferred orientation slender columnar grain containing with a multitude of deformation twins is formed in weld, which can reduce the number and proportion of high angle grain boundary, attributing to the elimination of solidification cracks and the enhancement of tensile strength.

The Cu-Ni-Si alloy has widely applications in the lead frames and electronics industries due to its high strength and conductivity. In this work, hot deformation behavior of the Cu-1.5Ni-1.1Co-0.6Si and Cu-1.5Ni-1.1Co-0.6Si-0.1Cr alloys were investigated through the isothermal compression tests using the Gleeble-1500D thermo-mechanical simulator operating at the temperature ranging from 500 °C to 900 °C and 0.001–10 s−1 strain rate. The deformed microstructure was characterized by the electron backscatter diffraction (EBSD) and the transmission electron microscopy. The constitutive equations of the alloys were established. According to the microstructure analysis, it can be observed that the grain size of the alloy with Cr was more uniform. In addition, the misorientation angle of 14.19 during recrystallization was significantly lower than 24 after the recrystallization, which means that the migration rate of grain boundaries is slow. The texture of the Cu-Ni-Co-Si alloy at 800 °C is the Goss {011}〈100〉 texture and {001}〈100〉 cubic texture, while the Goss texture at 900 °C is replaced by the {011} 〈112〉brass texture. The effects of Cr on precipitation phases were analyzed, and the precipitated phases were (Ni, Co)2Si, Co2Si. The addition of Cr promoted precipitation and significantly reduced the precipitate size. The addition of Cr can improve the strength and activation energy of the alloy. The activation energy was 569.8 kJ/mol and 639.5 kJ/mol, respectively.

To coordinate the supply chain risk caused by demand uncertainty, this paper proposed a flexible return strategy under demand uncertainty, in which the retailer can choose return quantity independently by put option after the selling season, while the return quantity is usually determined by the supplier in the classical return strategy. In our novel return strategy, the exercise price is not fixed, and we developed the base model of this strategy, named the selective buyback contracts model. We have solved the optimal pricing and ordering strategies of supply chain members. Numerical studies demonstrated that the contracts can coordinate a supply chain with one retailer and one supplier, and the supplier can adjust the profit distribution of the supply chain by adjusting the option exercise price. Compared with other return strategies, the selective buyback contracts give the retailer more power of choice, and the supplier receives risk compensation from the put options.

The evaluation of entrepreneurs’ uncertainty tolerance (UT) is more meaningful, e.g., predicting their behaviors, making psychological counseling strategies for them, etc. In fact, it is an uncertain problem that simultaneously contains randomness and fuzziness in evaluating entrepreneurs’ UT. Hence, it is difficult to solve it by traditional evaluation methods. This paper presents a cloud model-based comprehensive evaluation method for entrepreneurs’ UT which overcomes the inability of other methods to take into account randomness and fuzziness simultaneously. First, five UT levels are divided. Then, an evaluation index system which contains 14 secondary level indexes and four primary level indexes is constructed, and an analytic hierarchy process (AHP) method is used to obtain the weights for the secondary level indexes. Subsequently, the backward cloud generator (BCG) and virtual cloud model (CM) are used to obtain the CM of evaluation indexes, and cloud chart of evaluation results are generated by forward cloud generator (FCG). Finally, five core start-up founders of a high-tech company in China are chosen for a case study to illustrate our method. Compared with other traditional evaluation methods, our method has been verified to be a more competitive method. Its results are more visualized and low information lost.

Abstract 53BP1 plays an important role in DNA double-strand break (DSB) repair and this activity is negatively regulated by its interaction with Tudor interacting repair regulator (TIRR). However, how the TIRR-53BP1 repair axis is regulated in response to DNA damage remains elusive. Here, we demonstrate that TIRR is translocated to the cytoplasm and degraded upon DNA damage. Ubiquitination of TIRR at lysine 187 by DTX3L is a critical process that regulates NHEJ pathway activity and PARP inhibitor sensitivity by facilitating XPO1-mediated TIRR nuclear export and degradation after DNA damage. We show that DTX3L is overexpressed in prostate cancers in patients and that decreased expression of TIRR due to DTX3L overexpression impairs the negative regulatory effect of TIRR on 53BP1, which consequently induces HR deficiency and chromosomal instability and sensitizes prostate cancer cells to poly (ADP-ribose) polymerase (PARP) inhibitors. Our work reveals a dual action of DTX3L on TIRR degradation and nuclear exportation and identifies DTX3L as an upstream regulator of the TIRR-53BP1 axis that governs DNA repair pathway choice and PARP inhibitor sensitivity. These findings suggest that TIRR ubiquitination and DTX3L overexpression could be viable biomarkers predicting PARP inhibitor sensitivity in cancers.