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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.

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.

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.

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.

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.

17α-methyltestosterone (MT), as a synthetic androgen, has been widely used in medicine and aquaculture industry. However, the related molecular regulating mechanism of MT effects on hypothalamic-pituitary-gonadal axis has not been well addressed. This study first evaluated the effects of MT treatment on pituitary of mandarin fish (Siniperca chuatsi). Transcriptome analysis revealed a lot of differentially expressed genes were found in pituitary after MT treatment in early stage (10 and 20 dat), with a relatively few genes found in late stage (30 and 40 dat). Among them, several reproduction related genes were significantly upregulated after MT treatment, while only the expression of follicle-stimulating hormone beta submit (fshb) was significantly inhibited in all stages. Moreover, in vitro experiment also revealed MT significantly inhibited the expression of fshb and promoted the expression of androgen receptors in pituitary. However, dual-luciferase assay revealed that MT activated the promotor activity of fshb via androgen receptors. Finally, we also demonstrated FSH could directly activate the promotor of cyp19a1a by several ways. In all, we first demonstrated exogenous MT could inhibit the expression of fshb in pituitary and further decrease the production of estrogen in gonad by FSH signaling pathway in mandarin fish.

The objective of this study is to investigate a viable and effective method for artificially breeding the mandarin fish (Siniperca chuatsi) in the out-of-breeding season. The mature development of the female mandarin fish's gonad was induced through precise control of water temperature. Measurements were taken during the temperature control period, including body weight, body height, ovulation rate, relative fecundity and gonadosomatic index (GSI). Serum hormone levels were assessed, and histological sections of gonadal tissues were tracked. Subsequently, a series of experiments were conducted to establish the optimal protocol for hormone-induced ovulation and artificial fertilization. The findings revealed that manipulation and elevation of the aquaculture water body temperature could effectively induce gonad development and maturation in mandarin fish. In the high temperature group (HT, water temperature maintained at 25 ± 1 ℃), 81.25 % of the experimental fish reached maturity within 20 days. Subsequent hormone injection resulted in successful ovulation, normal fertilization, and subsequent incubation of viable young fish. Furthermore, the outcomes of the ovulation test using hormones demonstrated that the pairing of luteinizing hormone releasing hormone (LHRH-A2) and domperidone (DOM) proved highly effective in inducing ovulation in mature mandarin fish in the out-of-breeding season. The ideal dosage for a single injection of this combined hormone was determined to be 6 μg LHRH-A2 and 4 mg DOM / kg of body weight. Employing this optimal hormone dosage resulted in a fertilization rate of 83.23 %, a ovulation rate of 100 %, a relative fecundity of 93.40 ± 17.59 103 / kg and a hatching rate of 88.85 %. The anticipated outcome of these studies is to enhance the artificial breeding techniques for mandarin fish in commercial aquaculture, allowing for year-round production of fertilized eggs.

Summary: Background: The E1A-associated protein p300 (p300) has emerged as a promising target for cancer therapy due to its crucial role in promoting oncogenic signaling pathways in various cancers, including prostate cancer. This need is particularly significant in prostate cancer. While androgen deprivation therapy (ADT) has demonstrated promising efficacy in prostate cancer, its long-term use can eventually lead to the development of castration-resistant prostate cancer (CRPC) and neuroendocrine prostate cancer (NEPC). Notably, p300 has been identified as an important co-activator of the androgen receptor (AR), highlighting its significance in prostate cancer progression. Moreover, recent studies have revealed the involvement of p300 in AR-independent oncogenes associated with NEPC. Therefore, the blockade of p300 may emerge as an effective therapeutic strategy to address the challenges posed by both CRPC and NEPC. Methods: We employed AI-assisted design to develop a peptide-based PROTAC (proteolysis-targeting chimera) drug that targets p300, effectively degrading p300 in vitro and in vivo utilizing nano-selenium as a peptide drug delivery system. Findings: Our p300-targeting peptide PROTAC drug demonstrated effective p300 degradation and cancer cell-killing capabilities in both CRPC, AR-negative, and NEPC cells. This study demonstrated the efficacy of a p300-targeting drug in NEPC cells. In both AR-positive and AR-negative mouse models, the p300 PROTAC drug showed potent p300 degradation and tumor suppression. Interpretation: The design of peptide PROTAC drug targeting p300 is feasible and represents an efficient therapeutic strategy for CRPC, AR-negative prostate cancer, and NEPC. Funding: The funding details can be found in the Acknowledgements section.

Summary: Background: Finding the oncogene, which was able to inhibit tumor cells intrinsically and improve the immune answers, will be the future direction for renal cancer combined treatment. Following patient sample analysis and signaling pathway examination, we propose p21-activated kinase 4 (PAK4) as a potential target drug for kidney cancer. PAK4 exhibits high expression levels in patient samples and plays a regulatory role in the immune microenvironment. Methods: Utilizing AI software for peptide drug design, we have engineered a specialized peptide proteolysis targeting chimera (PROTAC) drug with selectivity for PAK4. To address challenges related to drug delivery, we developed a nano-selenium delivery system for efficient transport of the peptide PROTAC drug, termed PpD (PAK4 peptide degrader). Findings: We successfully designed a peptide PROTAC drug targeting PAK4. PpD effectively degraded PAK4 with high selectivity, avoiding interference with other homologous proteins. PpD significantly attenuated renal carcinoma proliferation in vitro and in vivo. Notably, PpD demonstrated a significant inhibitory effect on tumor proliferation in a fully immunocompetent mouse model, concomitantly enhancing the immune cell response. Moreover, PpD demonstrated promising tumor growth inhibitory effects in mini-PDX and PDO models, further underscoring its potential for clinical application. Interpretation: This PAK4-targeting peptide PROTAC drug not only curtails renal cancer cell proliferation but also improves the immune microenvironment and enhances immune response. Our study paves the way for innovative targeted therapies in the management of renal cancer. Funding: This work is supported by Research grants from non-profit organizations, as stated in the Acknowledgments.