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WC-Co cemented carbides, with low binder content (Co content <4 wt.%), have become prospects as ultra-precision cutting tool materials as a result of their high hardness, which can be ground to a sharp cutting edge when machining tools. In this paper, three cemented carbides, with Co content of 1 wt.%, 2 wt.% and 3 wt.%, were systematically investigated. The mode of preparation, properties, microstructure and ultra-precision turning of these cemented carbides were studied. It has been researched that 0.1 wt.% VC could effectively refine the WC grains to exhibit excellent properties. The optimum sintering temperatures for WC-1Co-VC, WC-2Co-VC and WC-3Co-VC were 1350, 1300 and 1300 °C, respectively. The resultant cemented carbides displayed extremely high hardness (2450, 2377 and 2325 kg/mm2), high relative density (>99%), specific fracture toughness (8.89, 9.01 and 10.17 MPa·m1/2) and transverse rupture strength (1274, 1387 and 1474 MPa). During oxidation, from room temperature to 400 °C, there was a slight reduction in the strength of the cemented carbides with no oxide formed. From 400 to 600 °C, their strength decreased significantly with apparent oxides formed on the surface. At 800 °C, all the cemented carbides experienced a severe drop in strength and massive oxidation on the surface and fracture surface. The cemented carbides were used to make cutting tools used for ultra-precision turning of brass. The surface roughness after machining with the three modified cemented carbide tools, with increasing Co content, were 22, 14 and 17 nm, respectively. [Display omitted] • Low binder WC-Co cemented carbide tool materials were prepared based on spark plasma sintering. • WC-1Co-VC, WC-2Co-VC, and WC-3Co-VC exhibited high hardness of 2450, 2377, and 2325 kg/mm2. • The transverse rupture strength and oxidation of three prepared cemented carbides were studied at high temperatures. • Ultra-precise turning of brass with prepared tools resulted in flat surfaces with surface roughness down to 14 nm. [ABSTRACT FROM AUTHOR]

Glioblastoma (GBM) is an incurable primary brain tumor that is highly resistant to current treatments. Glioma stem-like cells (GSCs) are an aggressive population of glioma cells that not only initiate malignant growth, but also promote therapeutic resistance. Thus, targeting GSCs is critical for improving GBM treatment and ensuring complete eradication of the tumor. Here, we show that NT5DC2 (5′-Nucleotidase Domain Containing 2), a functionally unknown protein, plays a crucial role in GSC tumor initiation via upregulating Fyn expression. NT5DC2 is preferentially expressed in GSCs relative to the non-stem tumor cells. Knockdown of NT5DC2 significantly inhibits the GSC tumorsphere formation and cell viability in vitro, and tumorigenesis in vivo, thus, prolonging animal survival. Moreover, disruption of NT5DC2 in GSCs markedly reduces the expression of Fyn, a Src family proto-oncogene that has been implicated in the regulation of GBM progression. Importantly, the expression of NT5DC2 strongly correlated with increased aggression of human gliomas, but not that of other brain tumors. Taken together, our results uncover the function of NT5DC2 in GSC maintenance and highlight NT5DC2 as a promising therapeutic target for GBM. • NT5DC2 is preferentially expressed in glioma stem-like cells. • NT5DC2 promotes glioma stem-like cells tumorigenesis. • NT5DC2 up-regulates Fyn expression in glioma stem-like cells. • NT5DC2 correlates with glioma malignant progression and patient survival. [ABSTRACT FROM AUTHOR]

Mercury is one heavy metal toxin that could cause severe health impairments. Mercury exposure has become a global environmental issue. Mercury chloride (HgCl 2) is one of mercury's main chemical forms, but it lacks detailed hepatotoxicity data. The present study aimed to investigate the mechanism of hepatotoxicity induced by HgCl 2 through proteomics and network toxicology at the animal and cellular levels. HgCl 2 showed apparent hepatotoxicity after being administrated with C57BL/6 mice (16 mg/kg.bw, oral once a day, 28 days) and HepG2 cells (100 μmol/L, 12 h). Otherwise, oxidative stress, mitochondrial dysfunction and inflammatory infiltration play an important role in HgCl 2 -induced hepatotoxicity. The differentially expressed proteins (DEPs) after HgCl 2 treatment and enriched pathways were obtained through proteomics and network toxicology. Western blot and qRT-PCR results showed acyl-CoA thioesterase 1 (ACOT1), acyl-CoA synthetase short chain family member 3 (ACSS3), epidermal growth factor receptor (EGFR), apolipoprotein B (APOB), signal transducer and activator of transcription 3 (STAT3), alanine--glyoxylate aminotransferase (AGXT), cytochrome P450 3A5 (CYP3A5), CYP2E1 and CYP1A2 may be the major biomarkers for HgCl 2 -induced hepatotoxicity, which involved chemical carcinogenesis, fatty acid metabolism, CYPs-mediated metabolism, GSH metabolism and others. Therefore, this study can provide scientific evidence for the biomarkers and mechanism of HgCl 2 -induced hepatotoxicity. • Oxidative stress, mitochondrial dysfunction and inflammation play an important role in HgCl 2 -induced hepatotoxicity. • Proteomics and network toxicology were combined for studying hepatotoxic mechanism. • ACOT1, ACSS3, EGFR, APOB, STAT3, AGXT, CYP2E1 and 3A5 may be the potential biomarkers for HgCl 2 -induced hepatotoxicity. [ABSTRACT FROM AUTHOR]

The Junggar Basin is one of the most important basins for hydrocarbon production in China. Within the basin, the Chunfeng Oilfield forms one of the most important oilfields of the area. Despite the significant work that has been done on the rocks of the oilfield so far, a detailed reservoir characterization and description of the hydrocarbon accumulation pattern was still missing. Therefore, an investigation had been initiated to fill this gap in our understanding of the hydrocarbon reservoirs of the Junggar Basin. The results of this study show that the tuff and andesitic lava lithofacies exhibit the highest reservoir potential in the area. Apart from the lithofacies, the results of this study show that tectonic (formation of fault systems) and diagenetic (formation of solution pores) effects, and the development of a weathering crust are crucial factors that control the quality of the petroleum reservoirs of the oilfield. In addition, two possible geological models of petroleum accumulation in isolated volcanic rocks and sandstone (IVRS) and connected volcanic rocks and sandstone (CVRS) are presented. [ABSTRACT FROM AUTHOR]