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This study reports the preparation of medium-thickness aluminum/steel composite plates with different diffusion layers using rheological cast-rolling technology. The thermodynamic software and first-principles were employed to determine the effects of different silicon contents on the solidification process and mechanical properties of the 6061 aluminum/steel composite plates. The research revealed that the Fe2Al5 phase on the steel side possessed a tongue-like preferential growth at a silicon content of less than 1.2 wt%. A granular Al–Fe–Si phase was formed on the aluminum side of the diffusion layer when the silicon content exceeded the saturation solubility (1.8 wt%), which completely suppressed the tongue-like preferential growth of the Fe2Al5 phase. First-principles calculations revealed that the matrixes showed superior toughness in comparison to binary intermetallic compounds (IMCs), while the toughness of binary IMCs surpassed that of ternary IMCs. The mechanical properties showed that the shear strength of the sample prepared by rheological cast-rolling was higher than that of composite casting and close to that of composite rolling, reaching a maximum value of 73.4 MPa. The shear strength initially increased and then decreased with an increase in isothermal diffusion time, and the fracture location was transferred from the loose FeAl3 to the Fe2Al5 phase. An increase in silicon content resulted in a slight increase in the microhardness of the diffusion layer, a delay of the peak value of the shear strength, and a reduction in the gradient of the shear strength. A substantial decrease in peak shear strength was observed when the silicon content reached 1.8 wt%.

The water chiller using centrifugal compressor with gas bearing is an important development direction for building energy saving, but the additional refrigerant cycle for bearing and motor colling leads to more complex performance especially under the various operating condition. Based on the heating and cooling loads of a building in Nanjing and the local climate conditions, this paper innovatively establishes an air conditioning system model using centrifugal compressor with gas bearings (CCGB), and analyzes the performance of air-cooling and water-cooling methods. Considering the heating and cooling loads, the annual energy consumption of two systems was compared consider the climate condition. The results show that the COP of water-cooling system is larger than that of air-cooling system due to the better heat transfer condition. The larger power consumption of compressor for air-cooling system leads to the larger motor cooling load. The cooling methods have obvious influence on the vapor-injected mass flow rate, but have small impact on the mass flow rate of motor cooling and bearing gas supply. The energy efficiency of air-cooling and water-cooling system in summer are 3.77 and 5.12 respectively, and the total energy consumption in the whole year are 32.4 tons and 33.5 tons of standard coal.

Study region: The Dajing and Xiaojing karst underground river system is the longest underground river in Guizhou Province, Southwest of China，located around the Five-hundred-meter Aperture Spherical radio Telescope (FAST). Study focus: The water quality of underground rivers around the FAST being affected by multiple anthropogenic activities. The underground river system is an extremely non-homogeneous and anisotropic media with complex hydrodynamic and hydrochemical responses. Multi-tools (hydrochemistry, water isotope, sulfur isotope and statistical methods) were applied to accurate identification and quantification of the proportions, spatiotemporal evolution and mechanisms of karst aquifer impacted by different anthropogenic activities. New hydrological insights for the region: The synchronous variations of δ18O, δD, d-excess and δ34SO42- in the effluent and the underground rivers suggested that the underground rivers are influenced by anthropogenic activities. The relationships of ionic ratios revealed that agricultural activities, effluent from the sewage treatment plant, and water-rock interactions control the hydro-chemical characteristics of the underground river system with a distinct spatiotemporal differentiation. The response time for the water quality of Dajing and Xiaojing underground river to anthropogenic impacts were 24 and 27 days, respectively. Spatially, the PCA-ACPS-MLR and MixSIAR indicated that more impacts of anthropogenic activities on Xiaojing underground river than Dajing underground river system. A quantification of spatiotemporal response differentiation provides new insights into the precise identification and prevention of pollution in karst underground rivers.

The as-cast Mg–2Y-0.5Zn-0.5Ni-0.5Co alloy (MYZNC, at%) underwent composite hot working, extrusion and rolling to further improve the mechanical properties, and the corresponding microstructure and mechanical properties were also investigated. The extruded and rolled MYZNC alloy (MYZNC-R) consisted of α-Mg, a long period stacking order (LPSO) phase comprising lamellar and fine block 18R LPSO phase as well as a thin strip 14H LPSO phase, along small amounts of Mg2Y, MgY(Co,Zn,Ni)4 and Mg3(Co,Zn,Ni,Y) particle phases. After composite processing, the dispersion and amounts of LPSO phase in the alloy was significantly enhanced, accompanied by a substantial introduction of low angle grain boundaries (LAGBs) during rolling process. The MYZNC-R alloy exhibited the high mechanical properties, with an ultimate tensile strength (σb) of 350 MPa, a yield strength (σ0.2) of 305 MPa and an elongation to failure (εf) of 10.6 %. In comparison to the extruded MYZNC alloy, both σb and σ0.2 demonstrated significant improvements by 25 % and 35.6 %, respectively. The elongation to failure only decreased by mere 1 %, indicating that the alloy had a good strength-plasticity. The high tensile strengths of MYZNC-R alloy were mainly attributed to grain refinement, LPSO phase strengthening and texture strengthening. The good ductility of MYZNC-R alloy was associated with the coordinated deformed LPSO phase and the formation of a high-volume fraction (∼76.5 %) of LAGBs.

Metabolic reprogramming is an essential hallmark of cancer. Several studies have reported the dysregulation of acylcarnitine (ACar) metabolism in tumor cells, suggesting that changes in the blood ACar may be related to tumor growth. Accordingly, this study aimed to understand the alteration of serum ACar profiles in various solid tumors and explore the potential of differential serum ACars as diagnostic biomarkers. A series of 69 relatively abundant ACars were identified via untargeted analysis. Then, targeted metabolomics was used to describe the metabolic alterations in ACars between normal controls and patients with six types of solid tumors. The results suggested that changes in ACars correlated with their carbon chain length and saturation. The six tumor types had highly similar ACar metabolic profiles, indicating similar fatty acid oxidation (FAO) metabolic pathways. Moreover, the receiver operating curve analysis of differential ACars showed that 16 ACars (C8–C14) had high diagnostic capability towards the studied solid tumors. Specifically, the area under the curve of ACar 10:2 isomer2 and ACar 12:2 isomer2 was greater than 0.95. In conclusion, the marked decrease in the levels of medium- and long-chain ACars (C8–C18) in the six solid tumors suggests that they may have similar FAO-based metabolic pathways, which could afford a common target for cancer therapy. Additionally, 16 ACars (C8–C14) were identified as potential biomarkers for diagnosing six types of solid tumors.

The poor age-hardening response of Mg alloys limited their development and applications. In this study, the age-hardening response of Mg–7Sn alloy has been improved significantly by a 40 MPa compressive stress aging at 220 °C. Phase transition from metastable βˈ (Mg3Sn) phase to β (Mg2Sn) phase occurs during the stress aging. The βˈ with L12 structure has an orientation relationship with the Mg matrix of (11¯0)β＇//(112¯0)α and [1¯1¯0]β＇//⌈0001¯⌉α. The precipitated sequence in the stress-aged alloy is S.S.S. (supersaturated solid solution)→GP→βˈ(Mg3Sn)→β(Mg2Sn). The stress-aged alloy exhibits a high peak-aged hardness (∼71 HV) and short time to reach the peak hardness (12 h) as compared with the aged alloy without the stress. Interestingly, a long-time aging platform with 71 HV for 96 h is observed during stress aging. The formation of the platform is related to a balance of hardening and softening arisen from microstructure evolution during stress aging. The stress aging provides a promising heat treatment way to improve aging hardening response of Mg alloys.

Stress aging is an effective method to improve age-hardening behavior of Mg alloys. In this paper, the stress aging was applied to improve poor age-hardening response of Mg–7Sn alloy. The age-hardening behavior, microstructure evolution and mechanical properties of Mg–7Sn alloy with an external compressive stress were investigated. The stress aging significantly altered the size, morphology, amounts and distribution of Mg2Sn phase. During the stress aging, micro/nano scale Mg2Sn particles precipitated on the basal plane of the stress aged alloy and their volume fraction remarkably increased as compared with the isothermal aging alloy. Interestingly, small amounts of Mg2Sn phases precipitated on the non-basal planes. The stress aging significantly reduced the peak aging time (96 h) and increased peak aging hardness (68.4 HV). The tensile tests showed that the stress peak-aged alloy at 80 MPa exhibited the highest tensile strengths (σ0.2 = 140 MPa and σb = 217 MPa), which were mainly attributed to the precipitation strengthening of Mg2Sn phase.

Effects of Zn addition on microstructure and mechanical properties of the extruded Mg97.8Y1.4Co0.8 (at.%, WC) alloy were investigated at room temperature. It was found that the as-cast WC alloy was mainly composed of α-Mg, MgYCo4, Mg3(Co,Y) and 15R-LPSO phases distributed at the grain boundary. All particles of as-homogenized WC alloy were remarkably refined after extrusion, but there was no phase transition during the subsequent homogenized and extruded states. With the replacement of Co from Zn, the as-cast Mg97.8Y1.4Co0.2Zn0.6 (at.%, WZC) alloy consisted of α-Mg, 18R-LPSO with lamellar and blocky shape, and a small amount of rich-Y phases. Parts of 18R-LPSO phases transformed into fine 14H-LPSO phases and stacking faults (SFs) in the grain interior during homogenization and extrusion. The extruded WZC alloy exhibited a smaller average grain size (∼3.2 μm) than the extruded WC alloy (∼3.9 μm) owing to fully dynamic recrystallization (DRX). Both the extruded WC and WZC alloys had a basal plane texture parallel to the normal direction (ND). Tensile testing results indicated that the Zn replacement improved tensile strengths of the extruded WC alloy and maintained the high elongation of the alloy (∼32.2%). The tensile yield strength, ultimate tensile strength and fracture elongation of the extruded WZC alloy were 212 MPa, 281.5 MPa and 32.2%, respectively. The alloy exhibited a good strength and ductility balance. The high tensile strengths of the extruded WZC alloy at room temperature were mainly attributed to grain refinement and the precipitation strengthening of different particles, and the good ductility was mainly due to grain refinement and texture weakening.

In this study, the pure Al and binary Al–Ni alloys with Ni addition of 1, 3, 6, and 10 wt % were coated via micro arc oxidation (MAO) in a tetraborate and phosphate based electrolyte for 60 min. With increased Ni content, the color of MAO coating became darker due to increased Ni-containing compounds on the surface. The Ni played a negative effect on the coating growth, decreasing both the coating thickness and surface roughness. The coatings on the Al–Ni alloys were mainly composed of γ-Al2O3 and α-Al2O3, and the Ni facilitated the formation of α-Al2O3 in the coating. Nanoparticles of NiO were generated around the edge of discharge channels for Al–6Ni and Al–10Ni alloys after a certain oxidation time. All coatings exhibited a uniform and dense surface structure, with the outer layer being more compact than the inner layer. Many tiny pores were found in the inner layer. Despite the corrosion resistance was decreased, the anti-wear performance of MAO treated samples was improved with the increased Ni content in the matrix. While, the corrosion resistance of the coated samples decreased with the adding of Ni content in the matrix.

Summary: Cervical cancer remains a significant health issue in developing countries. However, finding a preclinical model that accurately reproduces tumor characteristics is challenging. Therefore, we established a patient-derived organoids (PDOs) biobank containing 67 cases of heterogeneous cervical cancer that mimic the histopathological and genomic characteristics of parental tumors. The in vitro response of the organoids indicated their ability to capture the radiological heterogeneity of the patients. To model individual responses to adoptive T cell therapy (ACT), we expanded tumor-infiltrating lymphocytes (TILs) ex vivo and co-cultured them with paired organoids. The PDOs-TILs co-culture system demonstrates clear responses that correspond to established immunotherapy efficiency markers like the proportion of CTLs. This study supports the potential of the PDOs platform to guide treatment in prospective interventional trials in cervical cancer.

Introduction: The prognosis for cervical cancer (CC) patients with lymph node metastasis (LNM) is extremely poor. Lipid droplets (LDs) have a pivotal role in promoting tumor metastasis. The crosstalk mechanism between LDs and LNM modulated in CC remains largely unknown. Objectives: This study aimed to construct a miRNA-dependent progonostic model for CC patients and investigate whether miR-532-5p has a biological impact on LNM by regualting LDs accumulation. Methods: LASSO-Cox regression was applied to establish a prognostic prediction model. miR-532-5p had the lowest P-value in RNA expression (P

Novel valve spring blocking structure for generating pulsed waterjet was proposed, which belonged to interrupted type and purposed using in petroleum drilling. The characteristics and rock breakage performances of the pulsed waterjet were studied through experiments by changing its structural parameters. Results showed that the pulsed waterjet could be generated through the reciprocating motion of stem under the pressure difference and its rock breakage performance was better than continuous jet under the same conditions. The theoretical frequencies were slightly higher than the experimental value due to the ignorance of friction resistance between components and viscous resistance of fluid. The results provided a basis for its applications in petroleum drilling engineering.