University of Macau

About: University of Macau is a education organization based out in Macao, Macau, China. It is known for research contribution in the topics: Computer science & Population. The organization has 6636 authors who have published 18324 publications receiving 327384 citations. The organization is also known as: UM & UMAC.

Design and Performance of an Adaptive Low-DC-Voltage-Controlled LC-Hybrid Active Power Filter With a Neutral Inductor in Three-Phase Four-Wire Power Systems

Abstract: This paper proposes an adaptive low-dc-link-voltage-controlled LC coupling hybrid active power filter ( LC-HAPF) with a neutral inductor, which can compensate both dynamic reactive power and current harmonics in three-phase four-wire distribution power systems. Due to its adaptive low-dc-link-voltage characteristic, it can obtain the least switching loss and switching noise and the best compensating performances, compared with the conventional fixed and newly adaptive dc-voltage-controlled LC-HAPFs. The design procedures of the dc-link voltage controller are discussed, so that the proportional and integral gains can be designed accordingly. Moreover, the general design procedures for the adaptive dc-voltage-controlled LC-HAPF with a neutral inductor are also given. The validity and effectiveness of the adaptive dc-link voltage-controlled LC -HAPF with a neutral inductor are confirmed by experimental results obtained from a 220-V 10-kVA laboratory prototype compared with the conventional fixed and adaptive dc-link voltage-controlled LC-HAPFs without a neutral inductor.

Is a monetary union feasible for East Asia

Abstract: The empirical suitability of the East Asian economies for potential monetary integration is assessed. The structural vector autoregression (VAR) method is employed to identify the underlying shocks using a three-variable VAR model across the East Asian economies. The estimates of the EEC are used as a benchmark to compare the size of the underlying shocks and the speed of adjustment to shocks in both regions to determine the feasibility of forming an optimum currency area (OCA) in East Asia. The empirical results do not display strong support for forming an OCA in the East Asian region. The results do imply, however, that some small subregions are potential candidates for OCAs, since their disturbances are correlated and small and these economies adjust rapidly to shocks.

SIRT3 protects hepatocytes from oxidative injury by enhancing ROS scavenging and mitochondrial integrity

Abstract: Evidences of oxidative stress and mitochondrial dysfunction have been recognized in most of clinical and experimental liver diseases. SIRT3, a member of NAD+-dependent deacetylases, is mainly localized in mitochondria. So far, the role of SIRT3 in protecting hepatocytes against oxidative stress remains elusive. Herein, we found SIRT3 protein expression is decreased in tert-butyl hydroperoxide (t-BHP)-treated AML12 cells in vitro and primary hepatocytes from CCl4-injured mice in vivo. To further verify the role of SIRT3 in protecting hepatocytes from t-BHP-induced injury, SIRT3 overexpressed AML12 cell line and primary hepatocytes were generated. SIRT3 overexpressed hepatocytes showed improved cell viability upon t-BHP challenge, with less intracellular reactive oxygen species (ROS) accumulation. SIRT3 overexpression reduced superoxide dismutase 2 acetylation level and stimulated nuclear factor erythroid 2-related factor 2 nuclear translocation to enhance anti-oxidative capacity. Moreover, SIRT3 deacetylated peroxisome proliferator-activated receptor γ coactivator 1α to promote mitochondrial biogenesis, and 8-oxoguanine DNA glycosylase 1 to orchestrate DNA repair, resulting in improved mitochondrial function. Through deacetylating Ku70, SIRT3 also abated mitochondrial translocation of dynamin-related protein 1, to attenuate mitochondrial fragmentation in t-BHP-injured hepatocytes. These results suggested that SIRT3 protected hepatocytes against oxidative stress by enhancing ROS scavenging and maintaining mitochondrial integrity.

Factors that influence university students’ intention to use Moodle: a study in Macau

Abstract: Moodle is widely used in higher education institutions in this digital age. With the growing popularity of Moodle use in education, this study aimed to research on the factors that influence student users’ intentions to adopt Moodle for learning purposes in Macau. A total of 564 students from nine departments at the University of Macau responded to a survey in which ten constructs from a framework that integrated the Diffusion of Innovation Theory and Technology Acceptance Model, were measured. The results of this study showed that the research model had a good fit. Two variables—usefulness and ease of use—had significantly influenced Macau students’ attitudes towards Moodle use. Other variables such as usefulness, attitude, and perceived behavioral control were found to be important determinants of students’ behavioral intentions. Furthermore, usefulness was significantly associated with ease of use, output quality, trialability, as well as subjective norm. Students’ perceptions on the ease of use was significantly influenced by technology complexity and trialability. On the whole, the proposed research model had explained 66% of the variance of Macau university students’ behavioral intentions to use Moodle. This study contributed to deepening our understanding of technology acceptance theories by contextualizing the current study within the Macau higher education.