ALBERT

Description: Molecular beam epitaxy deposited rare-earth oxide of Y 2 O 3 has effectively passivated GaSb, leading to low interfacial trap densities of (1–4) × 10 12  cm −2  eV −1 across the energy bandgap of GaSb. A high saturation drain current density of 130  μ A/ μ m, a peak transconductance of 90  μ S/ μ m, a low subthreshold slope of 147 mV/decade, and a peak field-effect hole mobility of 200 cm 2 /V-s were obtained in 1  μ m-gate-length self-aligned inversion-channel GaSb p-Metal-Oxide-Semiconductor Field-Effect-Transistors (MOSFETs). In this work, high-κ/GaSb interfacial properties were better in samples with a high substrate temperature of 200 °C than in those with high κ's deposited at room temperature, in terms of the interfacial electrical properties, particularly, the reduction of interfacial trap densities near the conduction band and the MOSFET device performance.

Description: Production of hydrogen from water electrolysis has stimulated the search of sustainable electrocatalysts as possible alternatives. Recently, cobalt phosphide (CoP) and molybdenum phosphide (MoP) received great attention owing to their superior catalytic activity and stability towards the hydrogen evolution reaction (HER) which rivals platinum catalysts. In this study, we synthesize and study a series of catalysts based on hybrids of CoP and MoP with different Co/Mo ratio. The HER activity shows a volcano shape and reaches a maximum for Co/Mo = 1. Tafel analysis indicates a change in the dominating step of Volmer–Hyrovsky mechanism. Interestingly, X-ray diffraction patterns confirmed a major ternary interstitial hexagonal CoMoP 2 crystal phase is formed which enhances the electrochemical activity.

Description: Seismic hazard in the active collision zone of southeastern Taiwan has been poorly known. Although the area has experienced only a few magnitude 6 earthquakes during the modern seismic observation period, there are good geological and instrumental evidences that the area has repeatedly experienced magnitude 7 earthquakes, including a sequence in 1951. We estimated 3-D P- and S -wave velocity models by applying an earthquake tomography method to a large number of high-quality arrival-time data collected by a regional seismic network and a local seismic array. Earthquakes in the region that occurred between 1991 and 2011 were then relocated using the 3-D velocity models. The 3-D velocity models and seismicity depict the current deformation structures in the region. Numerous earthquakes have occurred along a narrow east-dipping seismic zone beneath the southern Coastal Range (CR) near Chengkung. The seismogenic structure extends from the surface eastward to depths greater than 20 km. It is characterized by low- V p , low- V s and low- V p / V s . Soft materials within the seismogenic structure may include fluids as well as cracks with high aspect ratios resulting from extended periods of tectonic loads. Soft sediments with high fluid contents between rigid materials are regarded as significant weak zones where stress concentration and nucleation of numerous earthquakes can easily occur. Beneath the western boundary of the Longitudinal Valley (LV), a vertical or steeply west-dipping strike-slip fault is identified. Apparently, significant slip partitioning is taking place to accommodate the oblique tectonic motions. In the eastern offshore, seismic velocities indicate that the materials are derived from deeper depth and that significant amounts of water have been introduced to form serpentines at shallow depth. The central LV and CR have been largely aseismic since a series of magnitude 7 earthquakes in 1951. A large amount of tectonic stress is stored in the region. Thus, the area has high potential to release seismic energy through future large earthquakes.

Description: Transarterial chemoembolization (TACE) is the main treatment for intermediate stage hepatocellular carcinoma (HCC) with Barcelona Clinic Liver Cancer classification because of its exclusive arterial blood supply. Although TACE achieves substantial necrosis of the tumor, complete tumor necrosis is uncommon, and the residual tumor generally rapidly recurs. We combined tirapazamine (TPZ),...

Description: Through the global supply chain (SC), numerous firms participate in vertically integrated manufacturing, and industrial collaboration and cooperation is the norm. SC management activities, such as delivery time, quality, and defect rate, are characterized by uncertainty. Based on all of the aforementioned factors, this study established a multiobjective mathematical model, integrating the guided genetic algorithm (Guided-GA) and the nondominated sorting genetic algorithm II (NSGA-II), developed in previous studies, to improve the mechanisms of the algorithms, thereby increasing the efficiency of the model and quality of the solution. The mathematical model was used to address the problems of supplier selection, assembly sequence planning, assembly line balancing, and defect rate, to enable suppliers to respond rapidly to sales orders. The model was empirically tested using a case study, showing that it is suitable for assisting decision makers in planning production and conducting SS according to sales orders, enabling production activities to achieve maximum efficiency and the competitiveness of firms to improve.

Description: Depletion of β-catenin impairs regeneration of the rapid turn-over gut epithelial cells, but appears dispensable for that of the slow turn-over mature hepatocytes in mice until 1 y of age. As the life span of mature murine hepatocytes is about 400 d, we studied conditional β-catenin knockout mice (Alb-Cre;Ctnnb1flx/flx) until 20 mo of age to determine the function of β-catenin in the postnatal liver. β-catenin was absent from the hepatocytes of β-catenin knockout mice 4 wk after delivery. From 9 mo of age, hepatocytes were gradually replaced by newly formed β-catenin-positive hepatocytes, which constituted about 90% of hepatocytes at 18–20 mo of age. This process was accompanied by active proliferation of bile duct/ductule cells. β-catenin-positive hepatocytes exhibited elevated proliferation activity and expression of progenitor cell markers, but lower albumin and Cre. This might explain their intact β-catenin protein, and suggest their origins from hepatic progenitor cells. Liver tumors arose spontaneously from β-catenin-positive cells, and tumorigenesis was accelerated by hepatitis B X protein. These results indicate β-catenin critical for the regeneration of mature hepatocytes. Failure to regenerate mature hepatocytes results in proliferation of hepatic progenitor cells that are able to maintain liver function but are predisposed to form liver tumors.

Description: Characterization of micro-patterned chemical vapor deposited monolayer graphene using a scanning microwave microscope has been presented. Monolayer graphene sheets deposited on a copper substrate were transferred to a variety of substrates and micro-patterned into a periodic array of parallel lines. The measured complex reflection coefficients exhibit a strong dependency on the operating frequency and on the samples' electrical conductivity and permittivity. The experiments show an extremely high sensitivity by detecting image contrast between single and double layer graphene sheets. Correlating the images recorded at the half- and quarter-wavelength resonant frequencies shows that the relative permittivity of the single layer graphene sheet is above 10 5 . The results are in good agreement with the three dimensional numerical electromagnetic simulations. This method may be instrumental for a comprehensive understanding of the scanning microwave microscope image contrast and provide a unique technique to estimate the local electrical properties with nano-meter scale spatial resolution of two dimensional materials at radio frequency.

Description: Motivation: The regulatory functions performed by non-coding RNAs are related to their 3D structures, which are, in turn, determined by their secondary structures. Pairwise secondary structure alignment gives insight into the functional similarity between a pair of RNA sequences. Numerous exact or heuristic approaches have been proposed for computational alignment. However, the alignment becomes intractable when arbitrary pseudoknots are allowed. Also, since non-coding RNAs are, in general, more conserved in structures than sequences, it is more effective to perform alignment based on the common structural motifs discovered. Results: We devised a method to approximate the true conserved stem pattern for a secondary structure pair, and constructed the alignment from it. Experimental results suggest that our method identified similar RNA secondary structures better than the existing tools, especially for large structures. It also successfully indicated the conservation of some pseudoknot features with biological significance. More importantly, even for large structures with arbitrary pseudoknots, the alignment can usually be obtained efficiently. Availability and implementation: Our algorithm has been implemented in a tool called PSMAlign. The source code of PSMAlign is freely available at http://homepage.cs.latrobe.edu.au/ypchen/psmalign/ . Contact: phoebe.chen@latrobe.edu.au Supplementary information: Supplementary data are available at Bioinformatics online.

Description: We apply several optical time-resolved techniques to investigate the dynamics of excess carriers in Al x Ga 1−x N nanocolumns grown on (111) silicon substrates and in thick Al x Ga 1−x N epitaxial layers deposited on sapphire. We demonstrate that carrier lifetime drops in nanocolumns by several times if compared to epilayers with similar Al content; in addition, recombination rate displays a strong nonlinearity on excitation. On the other hand, carrier localization effects observed in the epilayers completely disappear in nanocolumns.

Description: Populations of seasonal influenza virus experience strong annual bottlenecks that pose a considerable extinction risk. It has been suggested that an influenza source population located in tropical Southeast or East Asia seeds annual temperate epidemics. Here we investigate the seasonal dynamics and migration patterns of influenza A H3N2 virus by analysis of virus samples obtained from 2003 to 2006 from Australia, Europe, Japan, New York, New Zealand, Southeast Asia, and newly sequenced viruses from Hong Kong. In contrast to annual temperate epidemics, relatively low levels of relative genetic diversity and no seasonal fluctuations characterized virus populations in tropical Southeast Asia and Hong Kong. Bayesian phylogeographic analysis using discrete temporal and spatial characters reveal high rates of viral migration between urban centers tested. Although the virus population that migrated between Southeast Asia and Hong Kong persisted through time, this was dependent on virus input from temperate regions and these tropical regions did not maintain a source for annual H3N2 influenza epidemics. We further show that multiple lineages may seed annual influenza epidemics, and that each region may function as a potential source population. We therefore propose that the global persistence of H3N2 influenza A virus is the result of a migrating metapopulation in which multiple different localities may seed seasonal epidemics in temperate regions in a given year. Such complex global migration dynamics may confound control efforts and contribute to the emergence and spread of antigenic variants and drug-resistant viruses.