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ZnO nanorods were deposited on silicon substrate using sol-gel hydrothermal methods. The seed layer was first grown by solgel methods and then annealed at temperatures of 300°C, 400°C, 500°C and 600°C. Multiple material and optical analyses including fielde-mission scanning electron microscope, energy dispersive X-ray spectroscopy, X-ray diffraction, photoluminescence spectra, and Raman spectra were conducted to examine the growth orientation and material properties. Results indicate that the ZnO nanorods annealed at a proper temperature of 400°C could enhance orientation and material quality. [ABSTRACT FROM AUTHOR]

Backgrounds A new highly pathogenic human coronavirus (CoV), Middle East respiratory syndrome coronavirus (MERS-CoV), has emerged in Jeddah and Saudi Arabia and quickly spread to some European countries since September 2012. Until 15 May 2014, it has infected at least 572 people with a fatality rate of about 30% globally. Studies to understand the virus and to develop antiviral drugs or therapy are necessary and urgent. In the present study, MERS-CoV papain-like protease (PLpro) is expressed, and its structural and functional consequences are elucidated. Results Circular dichroism and Tyr/Trp fluorescence analyses indicated that the secondary and tertiary structure of MERS-CoV PLpro is well organized and folded. Analytical ultracentrifugation analyses demonstrated that MERS-CoV PLpro is a monomer in solution. The steady-state kinetic and deubiquitination activity assays indicated that MERS-CoV PLpro exhibits potent deubiquitination activity but lower proteolytic activity, compared with SARSCoV PLpro. A natural mutation, Leu105, is the major reason for this difference. Conclusions Overall, MERS-CoV PLpro bound by an endogenous metal ion shows a folded structure and potent proteolytic and deubiquitination activity. These findings provide important insights into the structural and functional properties of coronaviral PLpro family, which is applicable to develop strategies inhibiting PLpro against highly pathogenic coronaviruses. [ABSTRACT FROM AUTHOR]

Human cleavage and polyadenylation specificity factor (CPSF)73 (also known as CPSF3) is the endoribonuclease that catalyzes the cleavage reaction for the 30-end processing of premRNAs. The active site of CPSF73 is located at the interface between a metallo-ß-lactamase domain and a ß-CASP domain. Two metal ions are coordinated by conserved residues, five His and two Asp, in the active site, and they are critical for the nuclease reaction. The metal ions have long been thought to be zinc ions, but their exact identity has not been examined. Here we present evidence from inductively coupled plasma mass spectrometry and X-ray diffraction analyses that a mixture of metal ions, including Fe, Zn, and Mn, is present in the active site of CPSF73. The abundance of the various metal ions is different in samples prepared from different expression hosts. Zinc is present at less than 20% abundance in a sample expressed in insect cells, but the sample is active in cleaving a pre-mRNA substrate in a reconstituted canonical 30-end processing machinery. Zinc is present at 75% abundance in a sample expressed in human cells, which has comparable endonuclease activity. We also observe a mixture of metal ions in the active site of the CPSF73 homolog INTS11, the endonuclease for Integrator. Taken together, our results provide further insights into the role of metal ions in the activity of CPSF73 and INTS11 for RNA 30-end processing. [ABSTRACT FROM AUTHOR]

Resolving failure origins of AlGaN/GaN light emitting diodes (LED) has received intensive study recently. In this study, formation of GaCO3 caused by carbon contamination may result in deformation of the electrode near the surface and degrade the device. The electrochemical reactions may cause device damages. Degradation in electrical properties is observed in I-V characteristics. Forward-bias and reverse-bias EL images are used to trace the damaged areas. Furthermore, focus ion beam (FIB), scanning electron microscope (SEM), energy dispersive X-ray diffraction (EDX) are applied to examine the damaged areas. Results indicate that formation of GaCO3 may deform the electrode, generate the reverse-bias EL and cause the degradation. [ABSTRACT FROM AUTHOR]

ReS2 and ReSe2 have recently been enthusiastically studied owing to the specific in-plane electrical, optical and structural anisotropy caused by their distorted one-layer trigonal (1 T) phase, whereas other traditional transition-metal dichalcogenides (TMDCs, e.g. MoS2 and WSe2) have a hexagonal structure. Because of this special property, more and versatile nano-electronics and nano-optoelectronics devices can be developed. In this work, 2D materials in the series ReS2−xSex (0 ≤ x ≤ 2) have been successfully grown by the method of chemical vapor transport. The direct and indirect resonant emissions of the complete series of layers can be simultaneously detected by polarized micro-photoluminescence (μPL) spectroscopy when the thickness of the ReS2−xSex is greater than ∼70 nm. When it is less than 70 nm, only three direct excitonic emissions—E1ex, E2ex and ESex—are detected. For the thick (bulk) ReS2−xSex, more stacking of the ReX2 monolayers even flattens and shifts the valence-band maximum from Γ to the other K- or M-related points, thus leading to the coexistence of direct and indirect resonant light emissions from the c-plane ReX2. The transmittance absorption edge of each bulk ReX2 (a few microns thick) usually has a lower energy than those of the direct E1ex and E2ex excitonic emissions to form indirect absorption. The coexistence of direct and indirect emissions in ReX2 is a unique characteristic of a 2D layered semiconductor possessing triclinic low symmetry. [ABSTRACT FROM AUTHOR]

In this study, we address process how the ZnO nanorods were deposited on GaN substrates with spin-coating by using the hydrothermal methods. After ZnO was spin coated, the samples were annealed with different temperatures to incorporate with Au nano particles. Multiple material analyses, such as the field emission scanning electron microscopy (FESEM), the energy dispersive X-ray spectroscopy (EDX) and the X-ray diffraction (XRD) analyses were carried out to characterize the Au nanoparticles/ZnO nanorods/GaN nanocomposites. [ABSTRACT FROM AUTHOR]