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Cu2MgSnS4 (CMTS) nanoparticles are successfully prepared via a solvothermal approach. X-ray diffraction (XRD) and Raman reveal that pure zinc-blende CMTS phase is obtained. Scanning electron microscopy (SEM) shows that CMTS nanoparticles exhibit microsphere structure. The band gap of as-obtained CMTS nanoparticles is calculated to be 1.68eV, indicating a potential candidate for tandem solar cells. The degradation rate of methylene blue (MB) with under visible-light irradiation is about 87%, indicating that CMTS can be useful for effective visible-light photocatalyst. [ABSTRACT FROM AUTHOR]

Cu2ZnSn(S,Se)4 (CZTSSe) thin film deposited on flexible Mo foil substrate has advantage of high mass specific power and good ductility. However, a thick Mo(S,Se)2 interface layer is easily to be formed between CZTSSe and Mo foil substrate. The ohmic contact property of CZTSSe/Mo is deteriorated by the formation of Mo(S,Se)2. In this work, the Mo foil substrate was pre-annealed to inhibit the growth of Mo(S,Se)2 interface layer. CZTSSe thin films were prepared on the pre-annealed Mo foil substrate by sol-gel and selenization methods. The pre-annealing treatment of Mo foil substrate leads to the oxidation of Mo. During the high temperature selenization process, the MoOx acts as a buffer layer to suppress the formation of the Mo(S,Se)2 interface layer. With the increase of the pre-annealing temperature of the Mo foil substrate, the thickness of the Mo(S,Se)2 interface layer decreases, and the resistance of CZTSSe/Mo(S,Se)2/Mo structure decreases. The ohmic contact properties of CZTSSe/Mo can be improved by the pre-annealing treatment of metal Mo foil substrates. [ABSTRACT FROM AUTHOR]

OBJECTIVE: We aimed to construct/ validate a radiomics method based on MR FS-T2WI sequence for the evaluation of kidney function in patients with autosomal dominant polycystic kidney disease (ADPKD). PATIENTS AND METHODS: The clinical data and MRI images of 114 patients with ADPKD were retrospectively analyzed. With a glomerular filtration rate of 60 mL/min per 1.73 m2 as the cutoff value, patients were divided into two groups, where there were 59 patients with GFR ≥60 mL/min per 1.73 m2 (including CKD1 and CKD2 phase) and 55 patients with GFR <60 mL/ min per 1.73 m2 (including CKD3 phase and higher). All patients underwent the 3.0T MR scan of the kidney. Then, the kidney were delineated layer by layer based on the FS-T2WI sequence to obtain the volume of interest (VOI) for radiomics features extraction. The optimal radiomics features were selected by least absolute shrinkage and selection operator (LASSO). Three kinds of data modality including the pure clinical data, the pure image data and the clinical-image fused data were utilized to establish three types of models (clinical, image and with their combination) separately by five machine learning classifiers: k-nearest-neighbors (KNN), support vector machine (SVM), logistic regression (LR), random forests (RF) and multi-layer perception (MLP). Receiver operating characteristic (ROC) curve, areas under the curve (AUC), sensitivity, specificity and precision were employed to evaluate the model’s effectiveness to diagnosis the glomerular filtration rate of patients with ADPKD based on different models. Besides, Delong test was applied to compare ROCs between models. RESULTS: 9 60 r adiomics f eatures w ere e xtracted from each VOIs, and clinical information included the gender and age of each patient. After feature selection, 23 and 21 features based on pure image data and clinical-image fused data were independently used to construct models for the kidney function evaluation. The clinical-image fused model (AUC=0.89) has better performance than the pure image model (p=0.046) and pure clinical model (p<0.001). Clinical-image fused model based on LR classifier showed the best diagnostic efficiency, with AUC=0.89, sensitivity=0.8867 and specificity= 0.7959. CONCLUSIONS: The MR FS-T2WI radiomics analysis based on clinical-image fused model is instrumental in evaluating and predicting the kidney function of patients with polycystic kidney disease. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Non-small cell lung cancer (NSCLC) is the leading cause of cancer- related death worldwide. microRNAs (miRNAs) have been confirmed as vital regulators of multiple tumors, including NSCLC. The aim of the current study was to explore the biological mechanisms of miR-99b in NSCLC progression. PATIENTS AND METHODS: NSCLC tissues and adjacent matched human non-neoplastic lung tissues used in this study were collected from 50 cases of NSCLC patients. The expression of miR-99b and NIPBL in NSCLC tissues and cell lines (A549, NCI-H460, NCI-H1299 and SPC-A1) were determined by real-time-polymerase chain reaction (qRT-PCR). The NIPBL protein level was measured by Western blot. Dual-Luciferase reporter, Western blotting and qRT-PCR were carried out to verify the potential target of miR-99b. Transwell assay was used for investigating miR-99b effect on cell migration and invasion in NSCLC cells. RESULTS: The results of qRT-PCR indicated that the expression of miR-99b was downregulated in the NSCLC tissues and cell lines. Overexpression of miR-99b could significantly inhibit the invasion and migration capacities in NSCLC cells. Furthermore, we also determined that NIPBL was a direct target of miR-99b. Additionally, we found NIPBL was implicated in the suppressive effects on NSCLC cell invasion and migration mediated by miR-99b. CONCLUSIONS: In summary, miR-99b exerted anti-tumor functions in NSCLC via regulation of NIPBL, suggesting that miR-99b/NIPBL axis may be novel biomarkers for NSCLC treatments. [ABSTRACT FROM AUTHOR]

The white light luminescence is observed from the silica slides implanted by sequential Si+ and C+ ions or only by C+ ions followed by thermal annealing. In the photoluminescence (PL) spectra, their white emissions cover the whole visible spectral range from 350 to 800 nm. The influence of thermal annealing on the PL of the implanted samples was studied. The microstructural and optical analysis allow us to figure out the origin of the white light emission, which is mainly attributed to the emission of graphite like C clusters although the contributions from the emissions of the Si and SiC nanocrystals are also included. Compared to the white light emission of C+ implanted sample, the white light emission of Si+/C+ implanted sample has higher thermal stability. [ABSTRACT FROM AUTHOR]

OBJECTIVE: This study aimed to explore the effects of microRNA-29b (miR-29b) on chemoresistance of glioma and to examine the underlying mechanisms. MATERIALS AND METHODS: MiR-29b expression in glioma tissues and cell lines was analyzed by quantitative real time-polymerase chain reaction (qRT-PCR). The cell viability was determined by Cell Counting Kit-8 (CCK-8) assay. Cell apoptosis was analyzed by Annexin V-Fluorescein isothiocyanate (FITC) assay. The relationship between miR-29b and signal transducer and activator of transcription 3 (STAT3) was examined by the Dual-Luciferase reporter gene assay. The levels of cleaved caspase-3, Bax, Bcl-2, and STAT3 were detected by Western blotting assay. RESULTS: The expression of miR-29b was downregulated in glioma tissues compared to normal brain tissue. In addition, the expression level of miR-29b was lower in glioma tissues from patients at late stages (III and IV) compared with early stages (I and II). Besides, miR-29b expression was significantly lower in LN229, U87MG, and U251 cells compared to normal human astrocytes (NHA) cells. Moreover, our results showed that miR-29b expression in Temozolomide (TMZ)-resistance cell lines U251/TMZ and U87MG/TMZ was markedly lower than that of TMZ-sensitivity cell lines U251 and U87MG. The protein levels of STAT3 and the phosphorylation of STAT3 were increased in U251/TMZ and U87MG/TMZ compared to U251 and U87MG. When the expression of miR-29b was repressed, cell viability was increased. Meanwhile, cell apoptosis was reduced, the protein levels of cleaved caspase-3 and (Bcl-2 Associated X Protein) Bax were decreased, whereas the protein level of B-cell lymphoma 2 (Bcl-2) was increased. Moreover, the effects of miR-29b knockdown on the cell growth and apoptosis in U251 and U87MG cells were markedly attenuated by knockdown of STAT3. In TMZ-resistant U251/TMZ and U87MG/TMZ cells, transfection with miR-29b decreased cell growth, promoted apoptotic cell death, elevated the protein levels of cleaved caspase-3, and Bax protein, while downregulated Bcl-2 protein. As expected, the effect of miR-29b upregulation on cell growth and apoptosis of TMZ-resistant glioma cells was reversed by STAT3 overexpression. The results from the Luciferase assay demonstrated miR-29b modulated STAT3 expression by directly bound with 3'-Untranslated Region (3'-UTR). CONCLUSIONS: MiR-29b enhances the cell sensitivity to TMZ by inhibiting STAT3 in glioma. Our study might provide a novel target for treating TMZ-resistant glioma. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Islet beta cells are involved in insulin secretion. SRY-related high mobility group 9 (SX-S9) is involved in the progression of various diseases, but the role of SOX9 in islet β cells remains unclear. PATIENTS AND METHODS: The islet β cell MIN6 cells were cultured in vitro and randomly divided into control group, high glucose group, and SOX9 siRNA group followed by analysis of SOX9 mRNA and protein expression by real-time PCR and Western blot, respectively, cell proliferation by MTT assay, cell apoptosis by flow cytometry, secretion of inflammatory factors TNF-α and IL-2 by ELISA, insulin secretion levels by spectrophotometer, myeloperoxidase (MPO), and superoxide dismutase (SOD) activities, as well as ERK/P38 signaling protein expression by Western blot. RESULTS: Under high glucose environment, SOX9 mRNA and protein expression were significantly increased, MIN6 cell proliferation was inhibited, apoptosis rate and secretion of TNF-α and IL-2 were increased, along with decreased insulin secretion, increased MPO content, decreased SOD activity and phosphorylation of ERK/P38, compared with control group (p < 0.05). However, transfection of SOX9 siRNA reduced SOX9 expression, promoted proliferation of MIN6 cells, decreased apoptotic rate and secretion of TNF-α and IL-2, increased insulin secretion, decreased MPO content, increased SOD and ERK/P38 protein phosphorylation. Compared with high glucose group, the differences were statistically significant (p < 0.05). CONCLUSIONS: The expression of SOX9 is increased under high glucose environment. Down-regulation of SOX9 expression can inhibit islet cell apoptosis, oxidative stress and inflammation, and promote islet cell proliferation and insulin secretion by regulating ERK/P38 signaling pathway. [ABSTRACT FROM AUTHOR]

Based on the daily rainfall data of 19 meteorological stations in Guizhou Province from 1968 to 2017 and combining the characteristic of hydrogeology in Guizhou Province, this study revised the Dry-Wet Abrupt Alternation Index (DWAAI) and analyzed the spatial and temporal evolution characteristics of drought-flood abrupt alternation in Guizhou Province in recent 50 years. The results show that: 1. the revised DWAAI index has good applicability in Guizhou Province; 2) The time of drought-flood abrupt alternation is mainly distributed from April to October. In terms of the interannual variation, the station proportion and intensity show an increasing trend, and the increasing trend was significant in station proportion. The intensity of drought-flood abrupt alternation in autumn shows a decreasing trend, and the station proportion and intensity increase in other seasons, in which the intensity of the drought-flood abrupt alternation in spring and summer and the station proportion of the drought-flood abrupt alternation in summer increase significantly. (3) The frequency of the drought-flood abrupt alternation in Guizhou Province decreased from east to west as a whole. It is easy to occur in spring in the south, in summer in the middle and the north with the largest area, and in autumn in the east. With the increase of the years, the scope of prone areas has been expanding. The results are of great significance for disaster prediction and early warning and drought and flood control in this area. [ABSTRACT FROM AUTHOR]

Based on the extended finite element method (XFEM) and Wilson incompatible element technique, an incompatible extended finite element method (IXFEM) is presented to deal with the cracked bending problems in this study. The additional displacement modes of Wilson's incompatible element are introduced into the approximation of the XFEM. The internal degrees of freedom induced by additional models are condensed to improve efficiency. Derivation of the equilibrium equations of the IXFEM is performed. Several examples are employed to validate the capabilities of the proposed method. The influence of bending degree on the performance of proposed method is studied by changing the crack length. The numerical results indicate that the stress and displacement solutions of the IXFEM show a slight oscillation. The IXFEM achieves better convergence rate and computational accuracy compared with the traditional XFEM for the bending problems. [ABSTRACT FROM AUTHOR]