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Glioblastoma is one of the most frequent malignant tumors derived from the brain in adults with very poor prognosis. Ferroptosis is implicated in the initiation and progression of various tumors, including the glioblastoma. The present study aims to investigate the function of microRNA (miR)-670-3p in glioblastoma, and tries to demonstrate whether ferroptosis is involved in this process. Human glioblastoma cell lines, U87MG and A172, were transfected with the inhibitor, mimic and matched negative controls of miR-670-3p to manipulate intracellular miR-670-3p level. To validate the involvement of ferroptosis in miR-670-3p inhibitor-mediated tumor suppressive effects, ferrostain-1 and liproxstatin-1 were used to inhibit ferroptosis in the presence of miR-670-3p inhibitor. In addition, the small interfering RNA against acyl-CoA synthase long chain family member 4 (ACSL4) was used to knock down endogenous ACSL4 expression. To validate the combined effects between miR-670-3p inhibitor and temozolomide (TMZ), cells were pretreated with TMZ and then transfected with or without miR-670-3p inhibitor. miR-670-3p level was elevated in human glioblastoma, but decreased upon ferroptotic stimulation. miR-670-3p inhibitor suppressed, while miR-670-3p mimic promoted glioblastoma cell growth through modulating ferroptosis. Mechanistically, ACSL4 was required for the regulation on ferroptosis and growth of glioblastoma cells by miR-670-3p. Moreover, U87MG and A172 cells treated with miR-670-3p inhibitor showed an increased chemosensitivity to TMZ. We prove that miR-670-3p suppresses ferroptosis of human glioblastoma cells through targeting ACSL4, and that inhibiting miR-670-3p can be an alternative, at least adjuvant strategy to treat glioblastoma. [ABSTRACT FROM AUTHOR]

A novel method for the templated synthesis of the multi-layer graphene nanosheets in the curling layered nanostructure of halloysite nanotubes (HNTs) was developed. The intercalation of acrylamide in the layered nanostructure of HNTs was successfully achieved by the second-step substitution method. The formation of polymer precursor as carbon source exploited the in-situ polymerization of acrylamide in the layered nanostructure. A series of characterizations such as XRD, FT-IR, Raman, XPS, UV–vis, SEM, TEM and HRTEM were used to determine the formation of graphene nanosheets in the curling layered nanostructure of HNTs. The results indicated that the as-synthesized plane-like graphene nanosheets were originated from the unfolding of the spiral spring-like graphene formed in the curling layered nanostructure of HNTs. [ABSTRACT FROM AUTHOR]

[Display omitted] • The conventional minimum objective function with non-negative constraints is converted into an unconstrained maximization. • The novel inversion method is reliable to invert the TD-NMR signals with short relaxation time in low SNR. • The novel inversion method is verified by the measured data of fluid migrations in shales and cement hydration. The inversion of time-domain nuclear magnetic resonance (TD-NMR) signals is an ill-posed problem, which presents enormous challenges for the inversion algorithm. We propose a novel inversion method that converts conventional minimum objective function with non-negative constraints into an unconstrained maximization problem in the inversion of TD-NMR signals. Hence, the objective function becomes a differentiable concave function that can be solved more easily. The validity of the proposed method was verified by the uncertainty estimation of NMR inversion spectra with different signal-to-noise ratios (SNR). Through the inversion of simulated 2D D - T 2 and T 1 - T 2 signals under different SNR, the proposed method was proved to be less sensitive to noise than the conventional inversion method. We use the proposed method to study the migrations of oil and water in shales, the components change in shale could be identified and quantified according to the 2D T 1 - T 2 inversion spectra. The proposed method was also used to analyze the hydration process of cement. The 2D T 1 - T 2 inversion spectra could distinctly present the component of tiny volume with short relaxation time, and the migration regularity of capillary water, gel water, and bound water could also be found. In conclusion, the proposed method could be a reliable method to invert TD-NMR signals, especially the identification of the 2D NMR signals with a short relaxation time in low SNR. [ABSTRACT FROM AUTHOR]

An important application for discrete wavelet transform (DWT) is the image compression such as the JPEG2000 Standard, and GPU is a good choice for the implementation of the DWT. For the application of image compression in the space environment, this paper has discussed the fault tolerance for the forward DWT (FDWT) implemented on GPUs, to deal with the silent data corruption (SDC) errors caused by single event upsets (SEUs). This paper has analyzed the matrix descriptions for the procedures of the forward DWT in the JPEG2000 Standard. Using the matrix descriptions, the propagation of SDC errors in the multi-level forward DWT has been analyzed, and an algorithm-based fault tolerance (ABFT) method has been proposed, in addition, by analyzing the relationship between the data type and the SDC errors, an on-line fast error detection and correction method has been proposed to suppress the propagation of the logical value overflow errors. Finally, the performance of the program with ABFT has been evaluated and the overhead of memory space caused by the checksum data has been further analyzed. [ABSTRACT FROM AUTHOR]

In this letter, a transformed unsaturated inductance characteristic-based method is proposed for the rotor position of the switched reluctance machine. Due to the magnetic saturation effect, the phase inductance characteristics have a narrow linear region, which increases the difficulty of their analytical expression. To reduce the complexity of the analytical expression, the unsaturated inductance characteristic is transformed from the phase inductance characteristics. Then, a linear model is presented to explicitly describe the relationship between the rotor position and unsaturated phase inductance. Experimental verification is carried out to verify the effectiveness and accuracy of the proposed method. The proposed method can serve as a low-effort way to provide the accurate rotor position for the industry application at medium and high-speed ranges. [ABSTRACT FROM AUTHOR]

Industrial non-ferrous metal smelting and processing activities are a major contributor to the migration of arsenic-containing minerals throughout the environment, such as lollingite, which poses a severe threat to human health due to its rapid oxidation and subsequent release of arsenic (As). Herein, two phosphate mineral systems (potassium phosphate and calcium phosphate) were used to explore the potential for As solidification and establish the As immobilization mechanisms. Experimental results show that the compressive strength of the calcium phosphate system was higher than that of the potassium phosphate system due to the higher bond energy of the Ca–O–Mg–O–P–O system (31109 kJ / m o l), as compared to the K–O–Mg–O–P–O system (16189.2 kJ / m o l). Furthermore, the coordination capability of arsenic oxyanions with Ca or Fe ions was stronger than that of phosphorus oxyanions with Ca or Fe ions. The main mechanism of inhibition of As migration by magnesium phosphate cement (MPC) binders, was the formation of FeAsO 4.H 2 O, Ca 3 (AsO 4) 2.H 2 O, MgHAsO 4.H 2 O, CaMgAsO 4 (OH) and KMgAsO 4.6H 2 O coprecipitates, with physical encapsulation by MgKPO 4 ·6H 2 O (K-struvite), Ca 2 Mg(PO 4) 2 ·2H 2 O (Ca-struvite) and Mg 2 PO 4 (OH) phosphate-gel. Using Fe 2 O 3 -modified MPC binders with a Fe/As molar ratio of 3, the As immobilization efficiency reached 98.73%. The results of toxicity characteristic leaching procedure (TCLP) analysis confirmed that the maximum leached As concentrations from MPC binders cured for 7 days and 28 days were 0.31 mg/L and 0.06 mg/L, respectively, both of which were below the maximum permitted value for safe disposal (5 mg/L). These results verify the potential of MPC binders to be utilized as low-environmental impact and high-efficiency cementitious matrices for As pollution control and environmental remediation. [Display omitted] The highlights of our paper are. • The transformation and migration pathways of arsenic from lollingite to MPC binders was investigated. • Coprecipitation and physical encapsulation are the mechanisms to immobilize arsenic. • The coordination ability between As oxyanions and Ca or Fe ions, was stronger than that of phosphorus oxyanions. • The bond energy of the Ca–O–Mg–O–P–O system being stronger than that of the K–O–Mg–O–P–O system. • Fe 2 O 3 -modified MPC had excellent immobilization efficiency for As (99.9%). [ABSTRACT FROM AUTHOR]

To overcome the problems of steel slag (S-Slag) stockpiling and lead (Pb) contamination, in this study, a S-slag-metakaolin based geopolymer (SMBG) was prepared for the immobilization of Pb. The preparation conditions of SMBG were optimized by response surface methodology and immobilization mechanism of Pb was revealed. The optimum conditions for Pb immobilization calculated based on linear regression equations are as follows: S-Slag content 50.3 wt%, liquid–solid ratio 0.31, Baume degrees 51.2°Bé, and modulus 1.39. Under these optimum conditions, the 7-day compressive strength and Pb immobilization efficiency of SMBG were found to be 61.8 MPa and 99.99%, respectively. Subsequently, SMBG with different S-Slag contents were selected for analysis. The characterization analysis results showed that geopolymerization reaction of SMBG containing 50 wt% S-Slag was more complete, and produced more N–A–S–H gels and ettringite. Pb got immobilized in N–A–S–H gels and ettringite by physical encapsulation and ion exchange mechanism. Moreover, Pb reacts directly with silicates to form PbSiO 4 and Pb(OH) 2 precipitates. Further analysis shows that 15–25% of Pb in SMBG was present as precipitate or bound to hydration products, 25–30% of Pb was embedded in the aluminosilicate crystal structure, and the remaining Pb was present as covalent bonds. This study provides an effective solution for the harmless treatment of S-Slag and offers its potential applications in construction field. [ABSTRACT FROM AUTHOR]

In this work, graphene nanosheets (GN) have been successfully prepared under lower carbonization temperature by using the layered compounds CoAl-LDH. A series of characterizations such as XRD, FTIR, Raman TEM, SEM, EDX, XPS and UV–vis were used to verify the formation of graphene nanosheets in the layered structure of CoAl-LDH. It can be concluded that the Co element of layered double hydroxide acted as the catalytic centers in the formation of graphene nanosheets. [ABSTRACT FROM AUTHOR]

The clinical progression of small-cell lung cancer (SCLC) remains pessimistic. The aim of the present study was to promote the understanding of the clinical significance and mechanism of O-linked N-acetylglucosamine (GlcNAc) transferase (OGT) in SCLC. Wilcoxon tests, standardized mean difference (SMD), and Kruskal–Wallis tests were utilized to compare OGT level differences among the experimental and control groups. The univariate Cox regression analysis, Kaplan–Meier curves, and receiver operating characteristic curves were applied to determine OGT's clinical relevance in cancers. The Spearman correlation analysis and enrichment analysis were utilized to explore the underlying mechanisms of OGT in cancers. For the first time in the field, we provide an overview of OGT in 32 cancers using a large number of samples (n = 21,196), determining distinct OGT expression in 25 cancers and its prognosis effects in 12 cancers. Furthermore, using 950 samples from multiple sources, upregulated OGT was found in both mRNA and protein levels in SCLC (SMD = 0.93, 95% CI [0.24, 1.63]). Higher OGT levels represented a more unfavorable disease-free interval for SCLC patients (p < 0.001). The research also identified OGT expression as a potential marker for SCLC prediction (sensitivity = 0.79, specificity = 0.86, and AUC = 0.88). The high expression of OGT in SCLC may result from the positive regulation of two transcription factors—DEK and XRN2. We primarily investigated the underlying mechanisms of OGT in SCLC. Herein, based on the analyses from pan-cancer to SCLC, OGT demonstrated conspicuous clinical significance. OGT may be an underlying biomarker for the treatment and identification of some cancers, including SCLC. [ABSTRACT FROM AUTHOR]

Abstract A series of novel 2,4-disubstituted quinazolines were synthesized and evaluated for their anti-tumor activity against five human cancer cells (MDA-MB-231, MCF-7, PC-3, HGC-27 and MGC-803) using MTT assay. Among them, compound 9n showed the most potent cytotoxicity against breast cancer cells. Compound 9n also significantly inhibited the colony formation and migration of MDA-MB-231 and MCF-7 cells. Meanwhile, compound 9n induced cell cycle arrest at G1 phase and cell apoptosis, as well as increased accumulation of intracellular ROS. Furthermore, compound 9n exerted anti-tumor effects in vitro via decreasing the expression of anti-apoptotic protein Bcl-2 and increasing the pro-apoptotic protein Bax and p53. Mechanistically, compound 9n markedly decreased p -EGFR and p-PI3K expression, which revealed that compound 9n targeted breast cancer cells via interfering with EGFR-PI3K signaling pathway. Molecular docking suggested that compound 9n could indeed bind into the active pocket of EGFR. All the findings suggest that compound 9n might be a valuable lead compound for anti-tumor agents targeting breast cancer cells. Graphical abstract Image 1 Highlights • The 2,4-disubstituted quinazolines showed moderate to good growth inhibition against the tested five human cancer cells. • Among them, compound 9n exerted the most excellent anti-proliferative activities against breast cancer cells. • Compound 9n inhibited the colony formation and migration of MDA-MB-231 and MCF-7 cells. • Compound 9n caused cell cycle arrest at G1 phase and induced apoptosis of MDA-MB-231 and MCF-7 cells. • Compound 9n inhibited tumor growth through EGFR-PI3K signaling pathway. [ABSTRACT FROM AUTHOR]

The cracks in a rock tend to initiate, propagate, and coalesce under loading. Based on the digital image correlation (DIC) method, uniaxial compression tests are carried out on rock-like specimens with various arrangements of two parallel cracks. The full-field strain and failure features of the rock-like materials are observed and analysis by a self-developed code. Two process zones are defined according to the differences between the shear strain field and the tensile strain field: a shear process zone and a tensile process zone. The following results are obtained in this study. (1) Three coalescence modes can be observed using the DIC method: a shear coalescence mode, a tensile coalescence mode, and a mixed coalescence mode. (2) At the microscopic level, the bridge angle and crack arrangement affect the formation of the process zone; at the macroscopic level, they determine the crack propagation path and the failure mode. (3) The peak strength of the rock-like specimen is related to the crack inclination angle and the bridge angle. (4) Numerical modeling by the expanded distinct element method and the strain strength criterion simulates the different coalescence modes of the experimental study efficiently. [ABSTRACT FROM AUTHOR]

A digital image correlation (DIC) method was used to obtain the full-field strain and crack propagation path for a rock-like specimen with a single prefabricated crack under uniaxial compression. Additionally, scanning electron microscopy (SEM) was used to scan the fracture surface of the specimen after compression. The macro-mechanical response of the loading process was found to be in accordance with the micro-mechanism obtained by SEM, which demonstrates that the DIC system is accurate and that the full-field strain is accordant with crack propagation. Thereafter, a strain criterion was proposed and was applied to the extending discrete element method to simulate crack propagation. The strain criterion was found to be appropriate for simulating the crack initiation stress, peak strength and crack growth morphology of the specimen. Moreover, both the numerical simulation and experimental results show that the specimen failure process had four typical stages - initiation, unstable propagation, stable propagation and failure. [ABSTRACT FROM AUTHOR]

Modified biochars produced from different agricultural wastes were used as low-cost biosorbents to remove hydrophilic ionic liquid, 1-butyl-3-methyl-imidazolium chloride ([BMIM][Cl]). Herein, the biosorbents based on peanut shell, corn stalk and wheat straw (denoted as PB-K-N, CB-K-N and WB-K-N) all exhibited higher [BMIM][Cl] removal than many other carbonaceous adsorbents and the adsorption capacities were as the following: PB-K-N > CB-K-N > WB-K-N. The characterizations of biosorbents indicated that they had great deal of similarity in morphological, textural and surface chemical properties such as possessing simultaneously accessible microporous structure and abundant oxygen-containing functional groups. Additionally, adsorption of [BMIM][Cl] onto PB-K-N, CB-K-N and WB-K-N prepared from the modified process, which was better described by pseudo-second order kinetic and Freundlich isotherm models. Therefore, the viable approach could also be applied in other biomass materials treatment for the efficient removal of ILs from aqueous solutions, as well as recycling agricultural wastes to ease their disposal pressure. [ABSTRACT FROM AUTHOR]

The proper treatment of lollingite is of great significance due to its rapid oxidation leading to release of arsenic into the environment. Herein, a green multi-solid waste geopolymer, consisting of red mud, metakaolin, blast furnace slag, and flue gas desulfurization gypsum, was developed. The obtained red mud-metakaolin-based (RMM) geopolymer demonstrated good arsenic retention capability. The results showed that the replacement of SO 4 2− in ettringite with AsO 4 2− via ion exchange, formation of Ca-As and Fe-As precipitates, and physical encapsulation with aluminosilicate gel were the main mechanisms that prevented the release of arsenic. Further dissolution of ettringite in RMM was alleviated by adding a suitable amount of Ca(OH) 2 and controlling the pH of the leachate. TCLP results verified that RMM materials possessed an outstanding ability to stabilize arsenic, with a leaching rate below the permitted value of 5 mg/L for safe disposal. The low leachability of the RMM geopolymers (<0.50 mg/L) is potentially related to the pH buffering capacity of the hydration products at a pH range of 2–5. RMM geopolymers showed a high compressive strength (>15 MPa) and low arsenic leaching concentration (<2.66 mg/L) after 28 days of curing. These results demonstrate the potential of RMM geopolymers to be utilized as an environmentally friendly backfilling cementitious material for sustainable remediation of arsenic pollution. • The evolution pathways of arsenic from lollingite to RMM samples was investigated. • The dissolution of ettringite is correlated with the increase of As leachability. • Arsenic-bearing phases in RMM samples were demonstrated to be stable at pH 2–5. • RMM can be used as environmentally multi-solid waste cementitious material. [ABSTRACT FROM AUTHOR]

Transparent alumina with high transmission has been first successfully prepared by rapid vacuum pressureless sintering processing at lower sintering temperature and reduced soaking time, compared with conventional pressureless sintering. The alumina sintered at 1670°C for 5 min has a residual porosity of 0.002% and a real in-line transmission of 64% for a wavelength of 1100 nm. We show that soaking time has an effect on the densification and transparency of alumina sintered at 1650°C. With increasing sintering temperature and soaking time, densification and grain growth occurred, and above 20 min, grain size increases slowly. The real in-line transmission of alumina increased with the densification and decreased with pore size growth. The light transmission and absorption were greatly affected by the grain size and pore defects. [ABSTRACT FROM AUTHOR]

Summary [ABSTRACT FROM AUTHOR]

Abstract: To mimic the unique hierarchical structures of natural bone tissue, a novel hydroxyapatite (HA) composite coming from cormcob was synthesized by biomimetic method. Corncob, a natural porous material, was modified by phosphorylation with NaOH–H3PO4 methods. Subsequently, the phosphorylated samples were immersed in saturated Ca(OH)2 solution to be pre-calcified for 4 days, and then in a simulated body fluid (SBF) to be mineralized for 21 days. The results showed that bone-like apatite crystals formed both on the surface and inside the pores of the phosphorylated corncob. The apatite-corncob composite characterized with a hierarchical structure, and it is expected to be useful as a natural porous bioactive bone-repairing material. [Copyright &y& Elsevier]

The high temperature oxidation tests of Ni–Cr alloys which containing different alloying elements such as Mo, W, B, Cr and Ni were carried out through placing the specimen in a muffle for 100 h at 800 °C. In order to determine the effect of oxidation on the wear behavior of the alloys at elevated temperature, an interrupted oxidation-abrasion wear test was carried out on a high temperature three-body abrasive wear tester. Then the oxide and wear surfaces of the specimens were examined and the effect of the alloying elements on the oxidation and wear properties was discussed. Combining the obtained results, the following aspects are obtained. The high temperature oxidation stability of the carbide of the alloys can be improved by adding alloying elements Mo, W and B. And the sufficient amount of alloying elements Cr and Ni in the alloys can raise the chemical stability of the matrix effectively. The controlling factors affecting the wear behavior are the oxidation stability of carbide and the oxidation synergistic performance of carbide with matrix. The excellent wear resistant performance of the carbide phase in alloy can be obtained only when the matrix phase support it effectively. Accordingly, the alloy still can’t possess a good wear resistance when the oxidation synergistic performance of the carbide with matrix is poor, even the carbide oxidation stability is good. [Copyright &y& Elsevier]

We develop a rapid and convenient experimental method of absolutely calibrating the transmission of an x-ray flat-response filter. The calibration experiment is performed on a small laser-target facility, and a set of high resolution holographic flat-field grating spectrometers is used as a discrimination system of the laser-produced x-ray source. Given that the holographic flat-field grating has a relatively large width, the grating is divided into two regions for use in that direction, where one region has the filter added and the other region does not. The filter transmission is determined by dividing the x-ray signal counts detected when the filter is in the line of sight by those detected when the filter is out of the line of sight. We find that the calibration results of this experiment agree with the calibration results using a synchrotron radiation source, as well as simulation results. Our method is not only highly reliable but also rapid and convenient. [ABSTRACT FROM AUTHOR]