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The reduction roasting ammonia leaching process (RRAL) originally defined by Caron (1950) has been extensively applied to treat low grade nickel laterite and a large amount of slag-containing some valuable metals, has been generated and accumulated over the years since then. However, there are no reports on how to utilize it based on its essential properties. In this investigation, the textural and mineralogical characterization of the typical nickel slag from RRAL inWestern Australia was performed by X-ray diffraction (XRD), and scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS). The results show that the nickel slag is dominated by magnetite, maghemite, gangue minerals and minor Cr-spinel. The magnetite and maghemite possess simple distribution relationship with other minerals and their particles are highly variable with most over 50 μm, which are easily able to be recovered. In term of the complex association and distribution feature of chromium and nickel minerals, it is very difficult to recovery them. Meanwhile, an economically viable extraction process was proposed to preliminarily utilize the nickel slag based on textural and mineralogical characteristics of the slag, and the magnetic concentrate, assaying about 62% iron grade at over 75% recovery rate, was obtained through the recommended method. [ABSTRACT FROM AUTHOR]

The spatial distribution of automatic weather stations in regions of western China (e.g., Tibet and southern Xingjiang) is relatively sparse. Due to the considerable spatial variability of precipitation, estimations of rainfall that are interpolated in these areas exhibit considerable uncertainty based on the current observational networks. In this paper, a new statistical method for estimating precipitation is introduced that integrates satellite products and in situ observation data. This method calculates the differences between raster data and point data based on the theory of data assimilation. In regions in which the spatial distribution of automatic weather stations is sparse, a nonparametric kernel-smoothing method is adopted to process the discontinuous data through correction and spatial interpolation. A comparative analysis of the fusion method based on the double-smoothing algorithm proposed here indicated that the method performed better than those used in previous studies based on the average deviation, root mean square error, and correlation coefficient values. Our results indicate that the proposed method is more rational and effective in terms of both the efficiency coefficient and the spatial distribution of the deviations. [ABSTRACT FROM AUTHOR]

In this paper, an effective method was developed to remove phosphorus and upgrade iron from high phosphorus oolitic hematite ore by high temperature flash reduction--a wet magnetic separation process. A thermodynamic analysis of iron and phosphorus mineral reactions and experiments with Fe-P separation process were performed, and the mechanism of phosphorus removal and beneficiation of iron is discussed as well. The results show that under the proper conditions, a final metallic iron powder assaying over 91% Fe and 0.25% P was obtained with iron recovery of 90% and phosphorus removal rate of 91.79% using the new process, indicating that the high temperature flash reduction process is a feasible and efficient way to process this kind of complex and refractory iron ore. Moreover, sodium sulfate is found to be capable of improving the removal of phosphorus and the upgrading of iron, as well as enhancing the growth of metallic iron grains significantly for higher recovery of iron. [ABSTRACT FROM AUTHOR]

In the paper, a new technology was developed to improve the beneficiation of copper and iron components from copper slag, by modifying the molten slag to promote the mineralization of valuable minerals and to induce the growth of mineral grains. Various parameters, including binary basicity, dosage of compound additive, modification temperature, cooling rate and the end point temperature of slow cooling were investigated. Meanwhile, optical microscope, scanning electron microscope and energy dispersive spectrometer (SEM-EDS) was employed to determine the mineralogy of the modified and unmodified slag, as well as to reveal the mechanisms of enhancing beneficiation. The results show that under the proper conditions, the copper grade of rougher copper concentrate was increased from 6.43% to 11.04%, iron recovery of magnetic separation was increased significantly from 32.40% to 63.26%, and other evaluation indexes were changed slightly, in comparison with unmodified copper slag. Moreover, matte and magnetite grains in the modified slag aggregated together and grew obviously to the mean size of over 50 µm, resulting in an improvement of beneficiation of copper and iron. [ABSTRACT FROM AUTHOR]

The huge consumption of iron ores in China has attracted much attention to utilizing low grade complex iron resources, such as high-aluminum hematite-limonite ore, which is a refractory resource and difficult to upgrade by traditional physical concentration processes due to the superfine size and close dissemination of iron minerals with gangue minerals. An innovative technology for a high temperature reduction-magnetic separation process was studied to upgrade a high-aluminum iron ore assaying 41.92% Fetotal, 13.74% Al2O3 and 13.96% SiO2. The optimized results show that the final metal iron powder, assaying 90.46% Fetotal, was manufactured at an overall iron recovery of 90.25% under conditions as follows: balling the high aluminum iron ore with 15% coal blended and at 0.3 basicity, reducing the dried pellets at 1350 °C for 25 min with a total C/Fe mass ratio of 1.0, grinding the reduced pellets up to 95%, passing at 0.074 mm and magnetically separating the ground product in a Davis Tube at a 0.10-T magnetic field intensity. The metal iron powder can be used as the burden for an electric arc furnace (EAF). Meanwhile, the nonmagnetic tailing is suitable to produce ceramic, which mainly consists of anorthite and corundum. An efficient way has been found to utilize high-aluminum iron resources. [ABSTRACT FROM AUTHOR]

The malignant glioma remains one of the most aggressive human malignancies with extremely poor prognosis. Glioma cell invasion and migration are the main causes of death. In the current study, we studied the expression and the potential functions of tetraspanin 8 (Tspan8) in malignant gliomas. We found that Tspan8 expression level is high in both malignant glioma tissues and in several human glioma cell lines, where it formed a complex integrin α3 and rictor, the latter is a key component of mammalian target of rapamycin (mTOR) complex 2 (mTORC2). Disruption of this complex, through siRNA-mediated knockdown of anyone of these three proteins, inhibited U251MG glioma cell migration in vitro. We further showed that Tspan8-rictor association appeared required for mTORC2 activation. Knockdown of Tspan8 by the targeted siRNAs prevented mTOR-rictor (mTORC2) assembly as well as phosphorylation of AKT (Ser-473) and protein kinase C α (PKCα) in U251MG cells. Together, these results demonstrate that over-expressed Tspan8 in malignant glioma forms a complex with rictor and integrin α3 to mediate mTORC2 activation and glioma cell migration. Therefore, targeting Tspan8-rictor-integrin α3 complex may provide a potential therapeutic intervention for malignant glioma. [ABSTRACT FROM AUTHOR]

Alzheimer’s disease (AD) is a progressive neurodegenerative brain disorder characterized by memory loss, language impairment, personality changes and intellectual decline. Taking into account the key pathological features of AD, such as low levels of acetylcholine, beta-amyloid (Aβ) aggregation, oxidative stress and dyshomeostasis of biometals, a new series of paeonol derivatives 5a–5d merging three different functions, i.e., antioxidant, anti-acetylcholinesterase (AChE) activity, metal chelating agents for AD treatment have been synthesized and characterized. Biological assays revealed that compared with paeonol (309.7 μM), 5a–5d had a lower DPPH IC50 value (142.8–191.6 μM). 5a–5d could significantly inhibit hydrogen peroxide-induced neuronal PC12 cell death assessed by MTT assay in the concentration range of 5–40 μM. AChE activity was effectively inhibited by 5a–5d, with IC50 values in the range of 0.61–7.04 μM. 5a–5d also exhibited good metal-chelating ability. All the above results suggested that paeonol derivatives may be promising multifunctional agents for AD treatment. [ABSTRACT FROM AUTHOR]

This study proposes a dynamic hand gesture detection technology to effectively detect dynamic hand gesture areas, and a hand gesture recognition technology to improve the dynamic hand gesture recognition rate. Meanwhile, the corresponding relationship between state sequences in hand gesture and speech models is considered by integrating speech recognition technology with a multimodal model, thus improving the accuracy of human behavior recognition. The experimental results proved that the proposed method can effectively improve human behavior recognition accuracy and the feasibility of system applications. Experimental results verified that the multimodal gesture-speech model provided superior accuracy when compared to the single modal versions. [ABSTRACT FROM AUTHOR]

Histone modification enzymes regulate gene expression by altering the accessibility of promoters to transcription factors. We sought to determine whether the genes encoding histone modification enzymes are dysregulated in pediatric acute lymphoblastic leukemia (ALL). A real-time PCR array was designed, tested and used to profile the expression of 85 genes encoding histone modification enzymes in bone marrow mononuclear cells from 30 pediatric ALL patients and 20 normal controls. The expression profile of histone-modifying genes was significantly different between normal karyotype B cell pediatric ALL and normal controls. Eleven genes were upregulated in pediatric ALL, including the histone deacetylases HDAC2 and PAK1, and seven genes were downregulated, including PRMT2 and the putative tumor suppressor EP300. Future studies will seek to determine whether these genes serve as biomarkers of pediatric ALL. Ingenuity Pathway Analysis revealed that Gene Expression and Organ Morphology was the highest rated network, with 13 focus molecules (significance score = 35). Ingenuity Pathway Analysis also indicated that curcumin and miR-34 are upstream regulators of histone-modifying enzymes; future studies will seek to validate these results and examine the role of curcumin and miR-34 in leukemia. This study provides new clues into the molecular mechanisms of pediatric ALL. [ABSTRACT FROM AUTHOR]

This study proposes a dynamic hand gesture detection technology to effectively detect dynamic hand gesture areas, and a hand gesture recognition technology to improve the dynamic hand gesture recognition rate. Meanwhile, the corresponding relationship between state sequences in hand gesture and speech models is considered by integrating speech recognition technology with a multimodal model, thus improving the accuracy of human behavior recognition. The experimental results proved that the proposed method can effectively improve human behavior recognition accuracy and the feasibility of system applications. Experimental results verified that the multimodal gesture-speech model provided superior accuracy when compared to the single modal versions.