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• Al-7075 was reinforced by different contents of Fe-based metallic glass particles. • The composites were prepared by spark plasma sintering and hot extrusion. • The composites possess higher mechanical properties than unreinforced Al-7075. • The composites are reinforced mainly by thermal mismatch and grain refinement. Metallic glass (MG) reinforced aluminum matrix composites (AMCs) have attracted the interest of many researchers in the past few years. In this study, Fe 50 Cr 25 Mo 9 B 13 C 3 metallic glass (FMG) particles reinforced 7075 aluminum matrix (Al-7075) composites were prepared by spark plasma sintering (SPS) technique. The microstructure of the composites showed good interface bonding between the FMG particles and the matrix. The micro-hardness of the composite with 30 vol% FMG particles reached 160.63 HV, which was increased by 30% compared with that of Al-7075 (119.3 HV). The ultimate compression strength (UCS) of the composite was also improved significantly from 596 MPa for Al-7075 matrix to 749 MPa for the composite reinforced with 30 vol% FMG particles, and the compression strain of the composite reached 22%. These results indicate that the mechanical properties of the composites can be enhanced by adding high volume fraction FMG particles. The enhancement of the strength is resulted from multiple strengthening mechanisms, and the main contributions come from the thermal mismatch and grain refinement. [ABSTRACT FROM AUTHOR]

The carbon fiber reinforced silicon carbide matrix (C/SiC) composites were prepared by using precursor infiltration and pyrolysis method. Fracture characteristics of C/SiC materials were studied by single edge notched beam with the aid of digital image correlation (DIC) technique. It was found that DIC played an important role in in-situ monitoring full/local strain evolution and cracking growth during bending tests, which was useful for revealing potential failure micro-mechanisms of C/SiC composites. The results showed that the average fracture toughness KIC and fracture strength of C/SiC were estimated as 7.81±0.12 MPa m1/2 and 223.23±3.5 MPa, respectively. Moreover, the crack extension resistance curves (R-curve) in terms of stress intensity (KR-curves) were determined on the basis of the crack initiation toughness KIC. The values varied from 4.68 MPa m1/2 to 16.83 MPa m1/2 during the R-curve tests. [ABSTRACT FROM AUTHOR]

Urban air particulate pollution is a known cause for adverse human health effects worldwide. China has encountered air quality problems in recent years due to rapid industrialization. Toxicological effects induced by particulate air pollution vary with particle sizes and season. However, it is not known how distinctively different photochemical activity and different emission sources during the day and the night affect the chemical composition of the PM size ranges and subsequently how it is reflected to the toxicological properties of the PM exposures. The particulate matter (PM) samples were collected in four different size ranges (PM 10-2.5 ; PM 2.5-1 ; PM 1-0.2 and PM 0.2 ) with a high volume cascade impactor. The PM samples were extracted with methanol, dried and thereafter used in the chemical and toxicological analyses. RAW264.7 macrophages were exposed to the particulate samples in four different doses for 24 h. Cytotoxicity, inflammatory parameters, cell cycle and genotoxicity were measured after exposure of the cells to particulate samples. Particles were characterized for their chemical composition, including ions, element and PAH compounds, and transmission electron microscopy (TEM) was used to take images of the PM samples. Chemical composition and the induced toxicological responses of the size segregated PM samples showed considerable size dependent differences as well as day to night variation. The PM 10-2.5 and the PM 0.2 samples had the highest inflammatory potency among the size ranges. Instead, almost all the PM samples were equally cytotoxic and only minor differences were seen in genotoxicity and cell cycle effects. Overall, the PM 0.2 samples had the highest toxic potential among the different size ranges in many parameters. PAH compounds in the samples and were generally more abundant during the night than the day, indicating possible photo-oxidation of the PAH compounds due to solar radiation. This was reflected to different toxicity in the PM samples. Some of the day to night difference may have been caused also by differing wind directions transporting air masses from different emission sources during the day and the night. The present findings indicate the important role of the local particle sources and atmospheric processes on the health related toxicological properties of the PM. The varying toxicological responses evoked by the PM samples showed the importance of examining various particle sizes. Especially the detected considerable toxicological activity by PM 0.2 size range suggests they're attributable to combustion sources, new particle formation and atmospheric processes. [ABSTRACT FROM AUTHOR]

Graphene oxide-carbon nanotubes hybrid reinforced aluminum matrix composites (GO-CNT/Al) were prepared by powder metallurgy followed by hot extrusion. The strength of the composites was improved by the synergistic effect of carbon nanotubes, in-situ Al 4 C 3 and graphene oxide. Moreover, due to the partially recrystallization of Al matrix promoted by Al 4 C 3 , the matrix exhibits a bimodal grain distribution, which helps to enhance strain-hardening and consequently uniform tensile ductility at high flow stresses. Hence the bimodal grain structure of the matrix combined with the nano-reinforcements leads to enhancing of the strength and ductility synergy. The composite shows a high tensile strength of 249 MPa (175 MPa of pure Al) and keeps almost similar tensile ductility with pure Al (uniform elongation of ~23.1%). • The structure changes of graphene oxide and carbon nanotubes during ball milling were revealed. • The influence of reinforcement dimension on the strengthening mechanism of aluminum matrix composites was emphasized. • The balance between strength and ductility is achieved by different dimension reinforcements and bimodal grain distribution. [ABSTRACT FROM AUTHOR]

High elongation aluminum matrix composites reinforced with carbon nanotubes (CNTs) were prepared by flake powder metallurgy, and densified by hot extrusion with a high extrusion ratio. After hot extrusion, fine and equiaxed grains were obtained in 2 wt% CNT/Al composite, and interfacial product (Al 4 C 3) as well as bridge-connected CNTs aligned along the extrusion direction were found both in 1 wt% CNT/Al and 2 wt% CNT/Al composites. Both composites obtained high elongation while their strength was enhanced. Especially the elongation of 2 wt% CNT/Al composite is comparable to that of pure Al prepared by the same method, which reached about 30%. The good ductility mainly attributes to firm interfacial combination between CNTs and matrix, fine and equiaxed grains formed by dynamic recrystallization during hot extrusion, and bridge-connected CNTs aligned along the extrusion direction. Unlabelled Image • CNT/Al composites and pure Al were fabricated by flake powder metallurgy • The dynamic recrystallization occurred in 2 wt% CNT/Al composite during hot extrusion • The elongation of 2 wt% CNT/Al composite is comparable to that of pure Al prepared by the same method • The bridge-connected CNTs is helpful to improve the elongation of composite [ABSTRACT FROM AUTHOR]

• Compared with yellow wine lees mix, inclusion of fermented yellow wine lees mix into dairy diets improved lactation performance. • Inclusion of fermented yellow wine lees mix reduced the diet cost and increased the income of dairy farm. • Yellow wine lees mix and its fermented products had no adverse impacts on rumen fermentation and nitrogen utilization. Yellow wine lees (YWL) consist of a high content of crude protein with relatively low price. With microbial pretreatment, the increased crude protein content in the fermented YWL mix may be beneficial for the lactation performance of dairy cows. The current study was conducted to investigate lactation performance and nitrogen (N) utilization in lactating dairy cows receiving unfermented and fermented YWL mix as alternative protein source for soybean meal. Fifteen multiparous mid-lactation Chinese Holstein dairy cows with similar parity (2.30, SD 0.32), days-in-milk (190, SD 15.2) and milk yield (25.0, SD 0.45 kg) were used in a replicated 3 × 3 Latin square design. Diets were isonitrogenous and isocaloric, with a forage-to-concentrate ratio of 60:40 [dry matter basis]. Three dietary treatments were designed as follows (dry matter basis): (1) total mixed ration containing 18% soybean meal (Control), (2) total mixed ration containing 11% unfermented YWL mix (UM), and (3) total mixed ration containing 11% fermented YWL mix (FM). Each period lasted for 20 d, with the first 15 d used for adaptation and the next 5 d used for sampling. Dry matter intake (P = 0.04), milk yield (P = 0.02), milk protein yield (P = 0.02) and energy-corrected milk yield (P = 0.05) were higher in cows fed the control and FM diets than in those cows fed the UM diet. Milk composition, feed efficiency (milk yield/dry matter intake), and N conversion rate were not different (P > 0.05) among the three groups. The cows fed the UM diet showed lower N intake (P < 0.01), blood urea N (P = 0.02), urinary N (P = 0.04), microbial protein (P = 0.04) and metabolizable protein (P < 0.01) than the cows fed the control or FM diets. Feeding of the FM-fed cows tended to have greater IOFC than that of the control (P = 0.08), In summary, both unfermented and fermented YWL can be used as a protein source feed in the diets for lactating cows and inclusion of the fermented YWL had no adverse effects on lactation performance and N utilization but with greater profit. [ABSTRACT FROM AUTHOR]

The multikinase inhibitor sorafenib, and opening of voltage dependent anion channels (VDAC) by the erastin-like compound X1 promotes oxidative stress and mitochondrial dysfunction in hepatocarcinoma cells. Here, we hypothesized that X1 and sorafenib induce mitochondrial dysfunction by increasing reactive oxygen species (ROS) formation and activating c-Jun N-terminal kinases (JNKs), leading to translocation of activated JNK to mitochondria. Both X1 and sorafenib increased production of ROS and activated JNK. X1 and sorafenib caused a drop in mitochondrial membrane potential (ΔΨ), a readout of mitochondrial metabolism, after 60 min. Mitochondrial depolarization after X1 and sorafenib occurred in parallel with JNK activation, increased superoxide (O 2 •−) production, decreased basal and oligomycin sensitive respiration, and decreased maximal respiratory capacity. Increased production of O 2 •− after X1 or sorafenib was abrogated by JNK inhibition and antioxidants. S3QEL 2, a specific inhibitor of site IIIQ o, at Complex III, prevented depolarization induced by X1. JNK inhibition by JNK inhibitors VIII and SP600125 also prevented mitochondrial depolarization. After X1, activated JNK translocated to mitochondria as assessed by proximity ligation assays. Tat-Sab KIM1, a peptide selectively preventing the binding of JNK to the outer mitochondrial membrane protein Sab, blocked the depolarization induced by X1 and sorafenib. X1 promoted cell death mostly by necroptosis that was partially prevented by JNK inhibition. These results indicate that JNK activation and translocation to mitochondria is a common mechanism of mitochondrial dysfunction induced by both VDAC opening and sorafenib. [ABSTRACT FROM AUTHOR]

Aim: To retrospectively assess long-term survival benefit and safety of transcatheter arterial chemoembolization (TACE) combined with radiofrequency ablation (RFA) in hepatocellular carcinoma (HCC) patients with portal vein tumour thrombosis (PVTT), and to evaluate factors that significantly affect outcomes of these patients. Materials and methods: One hundred and thirty-four HCC patients (118 men and 16 women; mean age 54.8 years, range 26–79 years) with PVTT were retrospectively assessed. Patients were treated with TACE combined with RFA. Data analysed included patient demographics, liver volume, Child–Pugh score, and Cancer of the Liver Italian Programme (CLIP) score and imaging findings. Survival time (from occurrence of PVTT to last follow-up) was calculated using the Kaplan–Meier method, predictive factors and its correlation with survival was assessed using the multivariate Cox proportional hazards regression method. Results: The median overall survival (OS) time was 29.5 months (range 16.6–42.4 months), the 1, 3, and 5 year OS were 63%, 40%, and 23%. Cox hazards regression analysis revealed that functional remnant liver volume (FRLV), remnant liver volume (RLV)/total liver volume (TLV), radiation, tumour number, vascular endothelial growth factor (VEGF) distribution, and gross type were the only independent predictive factors of outcome (p = 0.039, 0.010, 0.009, 0.034, 0.031, and 0.000, respectively). Conclusion: TACE combined with RFA was found to be an effective therapy, FRLV and RLV/TLV have close correlation with survival for HCC patients with PVTT type I, II, or partial III and Child–Pugh A or B. [Copyright &y& Elsevier]