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Differently shaped two-dimensional (2-D) graphene nanoflakes (GNFs) were prepared on one-dimensional (1-D) carbon nanotubes (CNTs) and silicon nanowires (SiNWs) forming 2-D–1-D composites by using microwave plasma enhanced chemical vapor deposition. The GNFs are vertically aligned on 1-D nanomaterials with their sharp edges (less than 10 layers) unfolded outside and are rich in defects. GNF–CNT (or SiNW) composites with densely distributed and small-sized GNFs and not obviously thickened CNTs (or SiNWs) are found to have superior FE properties. The optimal FE performance obtained from the GNF–CNT composites shows a low threshold field of 1.54 V/μm and an extremely large maximum emission current density of 75.46 mA/cm 2 , far better than 1.77 V/μm and 27.90 mA/cm 2 for the pristine CNTs, respectively. The FE improvement is ascribed to the significant increase of active emission sites and also the preservation of the high aspect ratio of CNTs. Furthermore, longtime (30 h) stable FE is achieved from GNF–CNT composites with optimal shapes at a high mean emission current density of 45.47 mA/cm 2 and a low operation field of 1.766 V/μm, showing promising prospects in high-performance vacuum electronic device applications. [ABSTRACT FROM AUTHOR]

Sherman Alexie, a native American writer, applied successfully the magical realism in his Reservation Blues, in which he removed the mask of white colonists with a magic guitar and exposed the crime committed by the colonists to the Indians via two American military officers who rose again from death. Through such a narrative mode, the history that the Indians were deceived and suppressed by the white colonists and the current life of the residents in the Spokane Indian reservation were both revealed, as well as the key to the revitalization of Indians. As a novel with highly literary value in combination with sociological value, the Reservation Blues is one of the best works in native American literature. [ABSTRACT FROM AUTHOR]

In order to research the characteristic and mechanism of fracture of rock-like materials, the morphology of rock fracture surface under the breakages of uniaxial compression and triaxial compression was observed and measured by means of a new-type 3D laser scanning system. Based on geographic information system (GIS) technique, the fracture surfaces were 3D visualized and reestablished. According to GIS 3D statistics, the geometrical characteristics of fracture surfaces under different breakage conditions were analyzed, and then based on fractal theory, the change laws of fractal dimension of fracture surfaces were discussed under the conditions of different cell pressures and initial water contents of rock. Furthermore, the relationships between characteristics of fracture surface and mechanical properties of rock were discussed. The results indicate that cell pressure, initial water content, and mechanical parameters of rock are the important factors to influence on the geometrical characteristics of fracture surface. The research provides a new experimental method for quantitative study on the fracture characteristics of various materials under different breakage conditions. [ABSTRACT FROM AUTHOR]

Few-layer vertical graphene (VG) was prepared on arrayed carbon nanotubes (CNTs) without a catalyst by using radio frequency sputtering deposition and microwave plasma enhanced chemical vapor deposition, and the field emission (FE) performance of VG–CNT composites was tested and optimized. The FE performance is found to be strongly dependent on the heights (but not the actual heights) and densities of CNTs, the shapes of VG, and the diameters of VG–CNT composites. The optimal shapes for FE are demonstrated to be CNTs with middle densities and small diameters and VG with high densities and small sizes. The optimal FE performance from our large area VG–CNT composites is found to have a low threshold field of 1.28 V/μm (at 10 mA/cm 2 ), a high maximum emission current density of 87.63 mA/cm 2 (4.28 times higher than that from our previously prepared graphene–CNT composites), and excellent stability at an extremely high mean emission current density of 36.28 mA/cm 2 over a period of 50 h, far better than those of pristine CNTs, pure VG, and shape non-optimized VG–CNT composites. [ABSTRACT FROM AUTHOR]

Objective: To explore the significance of succinate dehydrogenase B (SDHB) mutation and EPAS1 overexpression in Zuckerkandl paragangliomas (PGL) and examine their correlations with malignant infiltration and metastasis., Methods: From March 2008 to July 2011, the clinical profiles of 16 Zuckerkandl PGL patients were analyzed retrospectively. For increased diagnostic specificity, a complex immunohistochemical panel of tissue microarray was performed for SDHB, EPAS1 and MIB-1. Positive expression identified as a granular cytoplasmic staining. Greater than or equal to 50% as strongly positive (+++), 1% to 10% as weakly positive (+)., Results: Tissue microarray immunohistochemical staining showed SDHB immunoreactivity in the cytoplasm, whereas EPAS1 and MIB-1 in the nuclear of tumor cells. Positive expression of EPAS1 in which 13 cases of Zuckerkandl PGL. And high expression strongly associated with malignancy. SDHB mutation of 7 cases are all EPAS1 positive staining. Non-gene mutation 9 cases tumor specimens, 6 cases were EPAS1 positive expression (P < 0.05). CgA positive expression in 11 cases benign Zuckerkandl PGL, strongly positive in 4 malignant cases (4/4). MIB-1 below 1% in 12 cases of benign Zuckerkandl PGL. And in 4 malignant cases, MIB-1 was about 3%. Malignant neoplasms had significantly higher EPAS1, CgA and MIB-1 expression compared to benign counterparts (P < 0.05)., Conclusions: The SDHB mutation causes the EPAS1 over expression in PGL and correlation with higher positive expression of CgA and MIB-1. It may be one of the mechanisms of malignant invasiveness and metastasis in PGL.

Renal cell carcinoma is one of the most common malignant tumors of urinary system. The annual incidence rate is approximately 17.9/100 000 populations, and there is a continually rising trend in number of new diagnosis. Metastatic and high-risk renal cell cancer is associated with a poor prognosis and is resistant to traditional chemotherapy and/or radiotherapy. Although cytokine-based therapies (interferon and interleukin-2) have been widely used, their effectiveness remained unsatisfactory due to their low response rates and short survival. Drugs targeting anti-angiogenesis pathways have shown benefits in relapse-free survival. In this review, we introduce the recent advances in the treatment of renal cancer, especially the application of vasculogenic mimicry and mosaic vessels. Although targeted therapies with anti-angiogenic properties have proposed new treatment criteria for advanced renal cell carcinoma, new drugs or new combinations are needed to improve the clinical efficacy and minimize adverse effects.

Background & Objective: Multidrug resistance plays an important role in chemotherapy failure of bladder cancer, but its mechanism is unclear. Hypoxia in tumors is generally associated with chemoresistance. However, the correlation of nuclear transcription factor hypoxia-inducible factor-1 (HIF-1) to multidrug resistance transporter glutathione-S-transferase-Pi (GST-Pi) has not been investigated. This study was to explore the expression and significance of GST-Pi and its correlation to HIF-1alpha in bladder carcinoma by tissue microarray., Methods: A tissue microarray containing 119 cases of bladder carcinoma and 6 cases of normal bladder tissue was built up. The expression of GST-Pi and HIF-1alpha was detected by SABC immunohistochemistry., Results: In the 119 cases of bladder carcinoma, the positive rate of HIF-1alpha was 57.9%, the positive rate of GST-Pi was 67.2%. The positive rate of HIF-1alpha in G3 grade bladder carcinoma was 64.6%. Their expression was closely related to pathologic grade, clinical stage, and postoperative relapse after adjuvant chemotherapy (P<0.01). HIF-1alpha expression was positively related to GST-Pi expression (P<0.01)., Conclusions: Overexpression of HIF-1alpha may be related to hypoxia. Co-expression of HIF-1alpha and GST-Pi is a object index for judging differentiation and chemoresistance of bladder cancer.

Background & Objective: Superficial transitional cell carcinoma (TCC) of urinary bladder tends to recur after transurethral surgery. This study was designed to evaluate the effect of interferon-alpha (IFN-alpha)and pirarubicin (THP) on decreasing postoperative recurrence of superficial bladder cancer., Methods: Recombinant IFN-alpha and THP has been used in clinical study. One week After operation, 68 patients were prospectively enrolled and divided into two groups randomly: IFN-alpha plus THP group and THP group. The protocols of chemoimmunoprophylaxis include 8 weekly and 10 monthly instillation of 3 x 10(7) IU IFN-alpha plus 40 mg THP in 40 ml 5% glucose via catheter., Results: The follow-up period ranged from 6 to 32 months (median 18.2 months). The cytoscopy and cytology with cold cup biopsies had been carried out every 3 months for 2 years. Recurrence after instillation of IFN-alpha combining THP was observed in only 4 cases (12.1%), bladder irritation was found in 4 cases, fatigue in 3 cases, and rash in 1 case as well. Among the 35 cases in THP group, recurrence was found in 8 cases (22.8%), bladder irritation in 5 cases, fatigue in 3 cases. IFN-alpha plus THP yielded better effect than THP alone (P< 0.05),especially in grade 3 and stage PT1 bladder cancer., Conclusions: IFN-alpha working in coordination with THP would be an effective remedy to prevent the recurrence of bladder cancer. The intravesical IFN-alpha plus THP appears to be more effective against recurrence than THP alone. Further study is needed for side-effect and popularization in such way.