3,442 research outputs found

    Academic experiences of international PhD students in Australian higher education: from an EAP program to a PhD program

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    For the last few decades, Australia has played a pivotal role in the supply of quality education to international students and other educational industries associated with them. In the higher education sector, in particular, international PhD student numbers continue to increase. However, the limited availability of resources for the students and the lack of investigation concerning the students indicate that there is a need for both higher education providers and other related stakeholders to understand and take into account the difficulties and challenges of international PhD students and their implications in the Australian academic context. While learning a new academic culture in a new country, international PhD students meet situations where they have to deal with a range of language problems, cultural differences and personal matters. The study reported in this article explores international non-English speaking background (NESB) students' experiences with university preparation programs and PhD programs and investigates the issues they face at an Australian university with a focus on factors affecting the NESB students' academic experiences. It provides implications for the teaching of postgraduate preparation programs and the supervision of international NESB PhD students at Australian universities

    On the existence of solutions of strongly damped nonlinear wave equations

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    We investigate the existence and uniqueness of solutions of the following equation of hyperbolic type with a strong dissipation: utt(t,x)−(α+β(∫Ω|∇u(t,y)|2dy)γ)Δu(t,x)                                −λΔut(t,x)+μ|u(t,x)|q−1u(t,x)=0,     x∈Ω,t≥0            u(0,x)=u0(x),          ut(0,x)=u1(x),      x∈Ω,  u|∂Ω=0, where q>1,λ>0,μ∈ℝ,α,β≥0,α+β>0, and Δ is the Laplacian in ℝN

    Applicability valuation for evaluation of surface deflection in automotive outer panels

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    Upon unloading in a forming process there is elastic recovery, which is the release of the elastic strains and the redistribution of the residual stresses through the thickness direction, thus producing surface deflection. It causes changes in shape and dimensions that can create major problem in the external appearance of outer panels. Thus surface deflection prediction is an important issue in sheet metal forming industry. Many factors could affect surface deflection in the process, such as material variations in mechanical properties, sheet thickness, tool geometry, processing parameters and lubricant condition. The shape and dimension problem in press forming is defined as a trouble mainly caused by the elastic recovery of materials during the forming. The use of high strength steel sheets in the manufacturing of automobile outer panels has increased in the automotive industry over the years because of its lightweight and fuel-efficient improvement. But one of the major concerns of stamping is surface deflection in the formed outer panels. Hence, to be cost effective, accurate prediction must be made of its formability. The automotive industry places rigi

    Subthreshold characteristics of pentacene field-effect transistors influenced by grain boundaries.

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    Grain boundaries in polycrystalline pentacene films significantly affect the electrical characteristics of pentacene field-effect transistors (FETs). Upon reversal of the gate voltage sweep direction, pentacene FETs exhibited hysteretic behaviours in the subthreshold region, which was more pronounced for the FET having smaller pentacene grains. No shift in the flat-band voltage of the metal-insulator-semiconductor capacitor elucidates that the observed hysteresis was mainly caused by the influence of localized trap states existing at pentacene grain boundaries. From the results of continuous on/off switching operation of the pentacene FETs, hole depletion during the off period is found to be limited by pentacene grain boundaries. It is suggested that the polycrystalline nature of a pentacene film plays an important role on the dynamic characteristics of pentacene FETs

    Downregulation of protein kinase CK2 activity induces age-related biomarkers in C. elegans

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    Studies show that a decrease in protein kinase CK2 (CK2) activity is associated with cellular senescence. However, the role of CK2 in organism aging is still poorly understood. Here, we investigated whether protein kinase CK2 (CK2) modulated longevity in Caenorhabditis elegans. CK2 activity decreased with advancing age in the worms. Knockdown of kin-10 (the ortholog of CK2 beta) led to a short lifespan phenotype and induced age-related biomarkers, including retardation of locomotion, decreased pharyngeal pumping rate, increased lipofuscin accumulation, and reduced resistance to heat and oxidative stress. The long lifespan of age-1 and akt-1 mutants was significantly suppressed by kin-10 RNAi, suggesting that CK2 acts downstream of AGE-1 and AKT-1. Kin-10 knockdown did not further shorten the short lifespan of daf-16 mutant worms but either decreased or increased the transcriptional activity of DAF-16 depending on the promoters of the target genes, indicating that CK2 is an upstream regulator of DAF-16 in C. elegans. Kin-10 knockdown increased production of reactive oxygen species (ROS) in the worms. Finally, the ROS scavenger N-acetyl-L-cysteine significantly counteracts the lifespan shortening and lipofuscin accumulation induced by kin-10 knockdown. Therefore, the present results suggest that age-dependent CK2 downregulation reduces longevity by associating with both ROS generation and the AGE-1-AKT-1-DAF-16 pathway in C. elegans. © Copyright 2017 Elsevier B.V., All rights reserved.1111sci

    Exposure to sound vibrations lead to transcriptomic, proteomic and hormonal changes in Arabidopsis

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    Sound vibration (SV) is considered as an external mechanical force that modulates plant growth and development like other mechanical stimuli (e.g., wind, rain, touch and vibration). A number of previous and recent studies reported developmental responses in plants tailored against SV of varied frequencies. This strongly suggests the existence of sophisticated molecular mechanisms for SV perception and signal transduction. Despite this there exists a huge gap in our understanding regarding the SV-mediated molecular alterations, which is a prerequisite to gain insight into SV-mediated plant development. Herein, we investigated the global gene expression changes in Arabidopsis thaliana upon treatment with five different single frequencies of SV at constant amplitude for 1 h. As a next step, we also studied the SV-mediated proteomic changes in Arabidopsis. Data suggested that like other stimuli, SV also activated signature cellular events, for example, scavenging of reactive oxygen species (ROS), alteration of primary metabolism, and hormonal signaling. Phytohormonal analysis indicated that SV-mediated responses were, in part, modulated by specific alterations in phytohormone levels; especially salicylic acid (SA). Notably, several touch regulated genes were also up-regulated by SV treatment suggesting a possible molecular crosstalk among the two mechanical stimuli, sound and touch. Overall, these results provide a molecular basis to SV triggered global transcriptomic, proteomic and hormonal changes in plant

    An Efficient and Secure m

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    Recent rapid developments in wireless and mobile IT technologies have led to their application in many real-life areas, such as disasters, home networks, mobile social networks, medical services, industry, schools, and the military. Business/work environments have become wire/wireless, integrated with wireless networks. Although the increase in the use of mobile devices that can use wireless networks increases work efficiency and provides greater convenience, wireless access to networks represents a security threat. Currently, wireless intrusion prevention systems (IPSs) are used to prevent wireless security threats. However, these are not an ideal security measure for businesses that utilize mobile devices because they do not take account of temporal-spatial and role information factors. Therefore, in this paper, an efficient and secure mobile-IPS (m-IPS) is proposed for businesses utilizing mobile devices in mobile environments for human-centric computing. The m-IPS system incorporates temporal-spatial awareness in human-centric computing with various mobile devices and checks users’ temporal spatial information, profiles, and role information to provide precise access control. And it also can extend application of m-IPS to the Internet of things (IoT), which is one of the important advanced technologies for supporting human-centric computing environment completely, for real ubiquitous field with mobile devices
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