Integrating constructivist approaches in e-learning to enhance mathematical self-study

E-learning models are currently practised widely all over the world due to the rapid growth of distance and global education. Furthermore, e-learning provides high quality educational offerings (Seufert 2002) and allows a convenient and flexible learning environment without restriction of learning space, distance and time (Albrechtsen et al. 2001). Hence, distance education is widely accepted by most of the nontraditional learners (Williams et al. 2002; Leonard & Guha 2001). Open University Malaysia (OUM) is one of the distance education universities in Asia that involves in hybrid concepts for learning. With advance media and communication technologies, OUM is capable of conducting courses using a combination of self-study process (provided with printed learning material), fortnightly face to face tutorials (five tutorials, two hours each per semester) and online communication (between studentsstudents and students-tutors)

Using E-learning to enhance the learning of graph transformations

Graphical representation of functions give more meaning to algebraic expressions and is suited to a particular mathematical task. Most of the distance students in Open University Malaysia (OUM) are unable to graph functions and cannot sufficiently understand graph transformations when taught through printed learning materials. Therefore, e-learning is recommended as an aid to enhance the learning of graph transformations for various types of functions. The objectives of the e-learning are to enable students to: 1) visualize graph transformations, 2) simulate graphical representations and 3) sketch functions with guidance. The e-learning develops in a natural progression from an animated presentation to guided and advanced level exercises. The elements of animation and interactivity create an educationally stimulating environment that can enhance the learning of mathematical issues and discovery of mathematical principles. This e-learning will be tested with the students in OUM to verify its effectiveness in the learning of functions and graph transformations. (Author's abstract

Does Hot Money Impact Stock And Exchange Rate Markets On China?

d the returns and volatility spillover between the stock and exchange rate market in China by using the monthly data covering the period from July 2005 to June 2013. This paper also uses the quantile approach to determine whether the hot money influences the stock and exchange rate markets. The results frst reveal the long-run equilibrium relationship that is exhibited between the stock and exchange rate market. Second, hot money has an impact on the stock market but has no effect on the exchange rate market, according to the VECMBEKK model. Third, regarding the volatility spillover effects on the stock and exchange rate markets, there is a spillover effect on the Shanghai stock and exchange rate markets. Hot money has an impact on the stock and exchange rate markets. Finally, we apply the quantile regression to determine the impact of hot money on low quantiles of the exchange rate and high quantiles of the Shanghai and Shenzhen stock marke

Bacteria in the apical root canals of teeth with apical periodontitis

Background/PurposeBacteria in the tooth root canal may cause apical periodontitis. This study examined the bacterial species present in the apical root canal of teeth with apical periodontitis. Antibiotic sensitivity tests were performed to evaluate whether these identified bacterial species were susceptible to specific kinds of antibiotics.MethodsSelective media plating and biochemical tests were used first to detect the bacterial species in samples taken from the apical portion of root canals of 62 teeth with apical periodontitis. The isolated bacterial species were further confirmed by matrix-assisted laser desorption ionization-time of flight mass spectrometry.ResultsWe found concomitant presence of two (32 teeth) or three species (18 teeth) of bacteria in 50 (80.6%) out of 62 tested teeth. However, only 34 bacterial species were identified. Of a total of 118 bacterial isolates (83 anaerobes and 35 aerobes), Prophyromonas endodontalis was detected in 10; Bacteroides, Dialister invisus or Fusobacterium nucleatum in 9; Treponema denticola or Enterococcus faecalis in 8; Peptostreptococcus or Olsenella uli in 6; and Veillonella in 5 teeth. The other 25 bacterial species were detected in fewer than five teeth. Approximately 80–95% of bacterial isolates of anaerobes were sensitive to ampicillin/sulbactam (Unasyn), amoxicillin/clavulanate (Augmentin), cefoxitin, and clindamycin. For E. faecalis, 85–90% of bacterial isolates were sensitive to gentamicin and linezolid.ConclusionRoot canal infections are usually caused by a mixture of two or three species of bacteria. Specific kinds of antibiotic can be selected to control these bacterial infections after antibiotic sensitivity testing

Lysophosphatidic Acid and Hematopoiesis: From Microenvironmental Effects to Intracellular Signaling.

Vertebrate hematopoiesis is a complex physiological process that is tightly regulated by intracellular signaling and extracellular microenvironment. In recent decades, breakthroughs in lineage-tracing technologies and lipidomics have revealed the existence of numerous lipid molecules in hematopoietic microenvironment. Lysophosphatidic acid (LPA), a bioactive phospholipid molecule, is one of the identified lipids that participates in hematopoiesis. LPA exhibits various physiological functions through activation of G-protein-coupled receptors. The functions of these LPARs have been widely studied in stem cells, while the roles of LPARs in hematopoietic stem cells have rarely been examined. Nonetheless, mounting evidence supports the importance of the LPA-LPAR axis in hematopoiesis. In this article, we have reviewed regulation of hematopoiesis in general and focused on the microenvironmental and intracellular effects of the LPA in hematopoiesis. Discoveries in these areas may be beneficial to our understanding of blood-related disorders, especially in the context of prevention and therapy for anemia

Dynamic Correlations and Volatility Spillovers between Crude Oil and Stock Index Returns: The Implications for Optimal Portfolio Construction

This paper researches the portfolio construction between stock price of group of seven (G7) and West Texas Intermediate crude oil from January 2, 1998 to March 1, 2012. We investigate the volatility spillover between stock price and oil price with the dynamic conditional correlation (DCC), constant conditional correlation (CCC) and BEKK models, and also analyze their optimal hedge ratio and portfolio weights. The empirical result is that the hedge effectiveness of DCC model is better than the CCC model and BEKK models. The hedge effectiveness (HE) in Canada is the highest but Japan is the lowest. Moreover, the results show that Japan has the biggest optimal portfolio weight and the lowest hedge ratio. We do this research with expectation of providing investors information to increase the basis of investing. Keywords: Crude oil; DCC model; Hedge effectiveness; Optimal portfolio JEL Classifications: C22; G1; N