Evaluating the somatically enhanced approach of teaching Mandarin Chinese

A tonal language such as Mandarin Chinese (MC) is considered a hard language to learn for English speaking learners. This paper reports on an experiment using the Somatically-Enhanced Approach (SEA) to teach MC in an Australian university. Innovations include: the use of relaxation, humming, clapping and gestures to emphasize the rhythm of MC

Crack initiation and propagation behaviour under high-temperature very-high-cycle fatigue: Directionally solidified columnar-grained vs. single-crystal superalloys

Role of oxidation and recrystallisation on very-high-cycle fatigue of columnar-grained DZ125 and single-crystal DD6 superalloys are investigated. With the temperature increase from 850 to 1000 °C for DZ125 while from 1000 to 1100 °C for DD6, the Mode-I cracking tendency increases due to internal oxide penetration. Recrystallisation can occur for both the electrolytically and mechanically polished surface conditions, controlled primarily by temperature and test duration. Its presence can lead to strain localisation at subsurface, but the surface recrystallisation does not necessarily determine the oxide penetration. By comparison with the single-crystal DD6 that shows the pure Stage I at 1000 °C, the columnar-grained DZ125 exhibits the distinctive Stage I cracking followed by Mode I propagation. This fracture characteristics in DZ125 can be attributed to the combined effect of the high-angle grain boundaries and far-field stress. The microstructure-related factor plays a vital role when the crack length is small, whereas the role of stress becomes predominant when the crack length is comparable to a couple of grains, ultimately leading to the shift from the crystallographic Stage I to Mode I propagation

Transition from internal to surface crack initiation of a single-crystal superalloy in the very-high-cycle fatigue regime at 1100 °C

Transition from internal to surface crack initiation is controlled by oxidation assisted fatigue-crack process in the very-high-cycle fatigue regime. Between 760 and 1000 °C, single crack initiation site is associated with internal casting defect, followed by a crystallographic Stage I propagation. By contrast, multiple surface crack initiation sites appear at 1100 °C, as the consequence of internal oxide penetration. The fatal crack follows a Mode I propagation and oxygen can diffuse into the material along the crack path. γ′-phase depletion appears surrounding the oxidised and cracked regions, while localised rafting can occur close to the crack tip

Feasibility Study of High-Velocity Oxy-fuel (HVOF) Sprayed Cermet and Alloy Coatings for Geothermal Applications

Geothermal is one of the least utilized renewable energy sources due to high investment costs and long development cycle. A major cost for geothermal operations is drilling, where the cost is dependent on drilling depth, tripping times, environments, etc. These costs can increase significantly for greater drilling depths, harsher environments, component failures, etc. During drilling, hammers break the rock through repetitive impact and cuttings are removed via a high-velocity stream. Component lifetime can be extended by selecting appropriate coatings resulting in reduced lost time and improved drilling efficiency. High-velocity oxygen fuel (HVOF) spraying is one of the most popular technique to deposit thick, dense and highly adherent coatings. This paper discusses the characteristics of cermet and alloy coatings using liquid-fueled HVOF spraying technique and their performance in simulated geothermal drilling environment. Properties of the deposited cermet (WC-CoCr, CrC-NiCr) and alloy (Ni self-fluxing, Fe-based amorphous) coatings in terms of surface roughness, thickness, porosity, hardness, adhesion strength, and erosion–corrosion resistance have been studied, and their performance are compared with selected benchmarking steel used in geothermal drilling. Based on the findings of this study, recommendations are made on the type of HVOF coatings that can potentially be used in geothermal applications.</p

A Fast-Acting Method for Simulating Precipitation During Heat Treatment of Superalloy 718

A fast-acting, mean-field method for simulating precipitation of the γ′′ and γ′ phases during aging of superalloy 718 following super-delta-solvus solution treatment was formulated and validated using observations in the literature. The approach assumed classical (homogeneous) nucleation and diffusion-controlled growth (N&G) of disk/ellipsoidal-shaped-γ′′ and spherical-γ′ particles. For the γ′′ precipitates in particular, the evolution equations for both nucleation and growth incorporated corrections for the non-spherical shape, assuming a fixed aspect ratio. In addition, special attention was paid to the choice of input material properties for simulations. These parameters included the bulk free energies of transformation, particle-matrix (misfit) elastic strain energy (for γ′′), effective diffusivities, and the γ′′–γ and γ′–γ interface energies. The applicability of the diffusivities and interface energies chosen for the N&G simulations was established by their consistency in replicating previously measured rate constants for the diffusion-controlled coarsening of both γ′′ and γ′. The N&G formulation was discretized to obtain numerical (spreadsheet) solutions via the Kampmann–Wagner approach. Simulation results for the temporal evolution of volume fraction and average size of the precipitates showed good agreement with experimental measurements. The sensitivity of model predictions to various input parameters was also quantified

The repetitive DNA landscape in Avena (Poaceae): chromosome and genome evolution defined by major repeat classes in whole-genome sequence reads.

BACKGROUND: Repetitive DNA motifs - not coding genetic information and repeated millions to hundreds of times - make up the majority of many genomes. Here, we identify the nature, abundance and organization of all the repetitive DNA families in oats (Avena sativa, 2n = 6x = 42, AACCDD), a recognized health-food, and its wild relatives. RESULTS: Whole-genome sequencing followed by k-mer and RepeatExplorer graph-based clustering analyses enabled assessment of repetitive DNA composition in common oat and its wild relatives' genomes. Fluorescence in situ hybridization (FISH)-based karyotypes are developed to understand chromosome and repetitive sequence evolution of common oat. We show that some 200 repeated DNA motifs make up 70% of the Avena genome, with less than 20 families making up 20% of the total. Retroelements represent the major component, with Ty3/Gypsy elements representing more than 40% of all the DNA, nearly three times more abundant than Ty1/Copia elements. DNA transposons are about 5% of the total, while tandemly repeated, satellite DNA sequences fit into 55 families and represent about 2% of the genome. The Avena species are monophyletic, but both bioinformatic comparisons of repeats in the different genomes, and in situ hybridization to metaphase chromosomes from the hexaploid species, shows that some repeat families are specific to individual genomes, or the A and D genomes together. Notably, there are terminal regions of many chromosomes showing different repeat families from the rest of the chromosome, suggesting presence of translocations between the genomes. CONCLUSIONS: The relatively small number of repeat families shows there are evolutionary constraints on their nature and amplification, with mechanisms leading to homogenization, while repeat characterization is useful in providing genome markers and to assist with future assemblies of this large genome (c. 4100 Mb in the diploid). The frequency of inter-genomic translocations suggests optimum strategies to exploit genetic variation from diploid oats for improvement of the hexaploid may differ from those used widely in bread wheat

Characterization of N-Glycan Structures on the Surface of Mature Dengue 2 Virus Derived from Insect Cells

<div><p>DENV envelope glycoprotein (E) is responsible for interacting with host cell receptors and is the main target for the development of a dengue vaccine based on an induction of neutralizing antibodies. It is well known that DENV E glycoprotein has two potential N-linked glycosylation sites at Asn67 and Asn153. The N-glycans of E glycoprotein have been shown to influence the proper folding of the protein, its cellular localization, its interactions with receptors and its immunogenicity. However, the precise structures of the N-glycans that are attached to E glycoprotein remain elusive, although the crystal structure of DENV E has been determined. This study characterized the structures of envelope protein N-linked glycans on mature DENV-2 particles derived from insect cells via an integrated method that used both lectin microarray and MALDI-TOF-MS. By combining these methods, a high heterogeneity of DENV N-glycans was found. Five types of N-glycan were identified on DENV-2, including mannose, GalNAc, GlcNAc, fucose and sialic acid; high mannose-type N-linked oligosaccharides and the galactosylation of N-glycans were the major structures that were found. Furthermore, a complex between a glycan on DENV and the carbohydrate recognition domain (CRD) of DC-SIGN was mimicked with computational docking experiments. For the first time, this study provides a comprehensive understanding of the N-linked glycan profile of whole DENV-2 particles derived from insect cells.</p></div

Hypoxia-induced Downregulation of SRC-3 Suppresses Trophoblastic Invasion and Migration Through Inhibition of the AKT/mTOR Pathway: Implications for the Pathogenesis of Preeclampsia.

Preeclampsia (PE) is characterized by poor placentation, consequent on aberrant extravillous trophoblast (EVT) cell function during placental development. The SRC family of proteins is important during pregnancy, especially SRC-3, which regulates placental morphogenesis and embryo survival. Although SRC-3 expression in mouse trophoblast giant cells has been documented, its role in the functional regulation of extravillous trophoblasts and the development of PE remains unknown. This study found that SRC-3 expression was significantly lower in placentas from PE pregnancies as compared to uncomplicated pregnancies. Additionally, both CoCl2-mimicked hypoxia and suppression of endogenous SRC-3 expression by lentivirus short hairpin RNA attenuated the migration and invasion abilities of HTR-8/SVneo cells. Moreover, we demonstrated that SRC-3 physically interacts with AKT to regulate the migration and invasion of HTR-8 cells, via the AKT/mTOR pathway. We also found that the inhibition of HTR-8 cell migration and invasion by CoCl2-mimicked hypoxia was through the SRC-3/AKT/mTOR axis. Our findings indicate that, in early gestation, accumulation of HIF-1α inhibits the expression of SRC-3, which impairs extravillous trophoblastic invasion and migration by directly interacting with AKT. This potentially leads to insufficient uterine spiral artery remodeling and placental hypoperfusion, and thus the development of PE

Relative expression levels of DENV-2 glycan binders by lectin microarray.

<p>The glycans binders were categorized into five types. (A) The GlcNAc binder DSA showed a stronger binding signal than the others. (B) (GlcNAc)n binders. (C) Bisecting and biantennary GlcNAc binders. (D) Mannose binders. (E) Gal binders. (F) Fucose binders. (G) Sialic acid binders.</p

N-Linked glycosylation status of purified DENV-2 was analyzed by SDS-PAGE and WB after PNGase F treatment.

<p>(A) Purified virus was observed by SDS-PAGE. (B) Purified virus was digested with PNGaseF (+) or mock digested (-) and evaluated by SDS-PAGE. (C) Western blotting was performed to show the deglycosylation patterns of envelope proteins of DENV-2 virions using anti-DENV-2 hyperimmune serum.</p