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Abstract Background Glutathione S-transferases (GSTs) play an important role in metabolizing anti-epileptic drugs (AEDs) in liver. Expressions of GSTs in brain, which may result in poor efficacy of AEDs, have not been well studied. Using clinical cortex specimen from 32 intractable epileptic subjects and 8 non-epileptic controls, the present study investigated the correlation between GSTs and intractable epilepsy. Results Three different GST isoforms (α, μ, and π) were detected with immunohistochemistry. GST-α expression was not seen in any cortex specimens. Sixty three percent (63%) of control and 53% of intractible epileptic specimens showed GST-μ immunoreactivity. No significant difference in intensity of GST-μ staining was observed between these two groups. GST-π expression was found in endothelial cells and glial cells/astrocytes. Fifty percent (50%) of the control patients and 66% of the epileptic patients were GST-π positive. The grading of epileptic patients was significantly higher than that of control patients (p < 0.01). Conclusion High levels of GST-π in endothelial cells and glial cells/astrocyte correlate to medical intractable epilepsy, suggesting that GST-π contributes to resistance to AED treatment.

A novel noncentrosymmetric (NCS) metal-free formic-borate, (NH4)3[B(OH)3]2(COOH)3, has been discovered, which exhibits an infrequent graphite-like structure. The alliance of two types of π-conjugated planar anions BO33− and COOH− produced an optimized layered structure to maximize the anisotropic polarizability, resulting in an extremely large birefringence (0.156@546 nm), larger than that of the classical commercial UV birefringent material α-BBO (0.122@546 nm). This strategy that structural optimization could enhance birefringence will guide the discovery of large birefringence materials, especially in the UV region. [ABSTRACT FROM AUTHOR]

User basic data (e.g. user gender, user age and user ID, etc.) and item basic data (e.g. item name, item category, etc.) are important side data that can be used to enhance the performance of recommendation algorithms, whereas attempts concerning this issue are still relatively scarce. In this study, a deep neural networks based recommendation algorithm is proposed where user average rating, user basic data (user gender, user age, user occupation, user ID), item basic data (item name, item category, item ID) and item average rating are used. The main idea of the algorithm is to build a regression model for predicting user ratings based on deep neural networks. For this, according to the user data (user average rating and user basic data) and the item data (items basic data and item average rating), a user feature matrix and an item feature matrix are respectively constructed using the four types of neural network layers [i.e., embedding layer (EL), convolution layer (CL), pooling layer (PL) and fully connected layer (FCL)]. Then, based on the obtained user feature matrix and item feature matrix, a user-item feature matrix is further constructed using a FCL. On this basis, a regression model for predicting user ratings can be trained, and a recommendation list can be generated according to the predicted user ratings. To verify the effectiveness of the proposed algorithm, three experiments are conducted using the real data from the MovieLens website. The results of experiments show that the proposed algorithm not only outperforms the state-of-the-art collaborative filtering (CF) recommendation algorithms but also alleviates the data sparsity problem and cold-start problem that would occur when the state-of-the-art CF recommendation algorithms are used. [ABSTRACT FROM AUTHOR]

Oxygen vacancies which are generally present in ferrite oxide may significantly affect their magnetic properties. A comprehensive understanding of the relationship between oxygen vacancies and magnetism is of great importance. In this work, we report an oxygen vacancy concentration dependence of magnetism in a single‐phase multiferroic BiFeO3 (BFO)‐based system. The BiFeO3‐DyFeO3 (BDFO) solid solution is synthesized with controlled oxygen vacancies and is characterized by X‐ray powder diffraction (XRD), X‐ray photoelectron spectroscopy (XPS), and AC impedance spectroscopy. The magnetic properties, especially magnetic pole inversion, are found to be highly dependent on oxygen vacancy concentration. The oxygen vacancies generate a Weiss molecular field on the Dy3+ ions in the magnetic field range of 570‐1000 Oe depending on the oxygen vacancy concentration, and result in a residual net magnetization by breaking the balance between the two nearly antiparallel spin lattices of Fe3+ ions. This work demonstrates an effective way to control oxygen vacancies and thereby the magnetic properties and sheds light on the relationship between oxygen vacancies and magnetism in BFO‐based multiferroics. [ABSTRACT FROM AUTHOR]

A novel antimony fluoride nitrate, Rb3SbF3(NO3)3, fabricated by a rational multi-component design, has been successfully synthesized by a rapid evaporation concentration method. This title compound crystallizes in a polar noncentrosymmetric (NCS) space group (P21) and presents a complicated three-dimensional (3D) network composed of SbO3F3, Rb-centered distorted polyhedra and π-conjugated planar triangular NO3 groups. Rb3SbF3(NO3)3 is a potential UV nonlinear optical material due to its large phase-matchable second harmonic generation (SHG) response of approximately 2.2 times that of KH2PO4 (KDP) and a wide band gap of 3.75 eV. Theoretical calculation analysis was used to rationalize the large SHG effect, which originates from the multi-component synergistic effect including moderately polarizable Rb+ cations, a stereochemically active lone pair effect of Sb3+ and NO3 groups with a π-conjugated planar triangular structure. [ABSTRACT FROM AUTHOR]

A series of BaGe(1−x)TixF6:Mn4+ solid solution phosphor crystals have been successfully synthesized by a facile hydrothermal method. The crystal structure, morphology and size of the obtained samples were characterized via X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. The influences of Ti4+ doping concentration on the microstructures and photoluminescent (PL) properties of the as-synthesized crystals were also investigated comprehensively. The XRD results indicate that all the as-synthesized BaGe(1−x)TixF6:Mn4+ samples are single phase solid solution crystals, although the doping concentration of Ti4+ has a remarkable influence on the lattice parameters. The SEM results reveal that all the as-synthesized BaGe(1−x)TixF6:Mn4+ phosphor samples are microcrystals with a predominant rod-like morphology and lengths ranging from 1 to 8 μm and widths ranging from 0.2 to 2.5 μm. The PL spectra reveal that all the obtained crystals exhibit characteristic emission peaks of Mn4+ ion, and the intensity of the strongest red emission peak located at 636 nm distinctly fluctuated with x, showing the highest at x = 0.6. Under excitation of 467 nm blue light, all the obtained BaGe(1−x)TixF6:Mn4+ samples can emit a warm red color, with a correlated color temperature (CCT) of less than 4500 K. The temperature-dependent PL emission spectra show that the BaGe0.4Ti0.6F6:Mn4+ sample possesses outstanding thermal stability, which can retain 62.27% of its initial emission intensity (323 K) even at 423 K. Employing the synthesized BaGe0.4Ti0.6F6:Mn4+ sample as a red component, a high-performance WLED with a correlated color temperature (CCT) of 4343 K, a color rendering index (CRI) of 93.2 and a luminous efficiency of 100.2 lm W−1 was obtained. Our findings suggest that BaGe(1−x)TixF6:Mn4+ can be a promising candidate as the red phosphor used in warm WLEDs. [ABSTRACT FROM AUTHOR]