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Papiliotrema huenov was previously reported to be highly tolerant of a range of extremely toxic heavy metals. This study aimed to identify the potential of P. huenov to remove manganese and copper from aqueous solution. Physical conditions which affect removal of Mn(II) and Cu(II) were determined. Optimal temperature for adsorption of both metal ions was 30 °C, and optimal pH for maximum uptake of Mn(II) and Cu(II) were 5 and 6, respectively. Under these conditions, living cells of P. huenov accumulated up to 75.58% of 110 mg/L Mn(II) and 70.5% of 128 mg/L Cu(II) over 120 h, whereas, the removal efficiency of metal ions by dead cells over 1 h was 60.3% and 56.5%, respectively. These results indicate that living cells are more effective than dead biomass for bioremediation, but that greater time is required. The experimental data extends the potential use of P. huenov in biosorption and bioaccumulation of toxic heavy metals to copper and manganese, two of the most common industrial contaminants.

Transnational education has experienced a phenomenal growth over the past decade. As a dynamic but complex phenomenon, transnational education involves the delivery of curriculum and educational pr...

Social networking websites are enjoying widespread usage throughout the world. Its applications are playing a significant role in marketing by allowing users to share information about products and...

Time-series and machine-learning methods are being strongly exploited to improve the accuracy of short-term load forecasting (STLF) results. In developing countries, power consumption behaviors cou...

With the rapid growth in the number of people using social networking sites, businesses are attempting to engage their customers by establishing social commerce websites, which provide customers wi...

The aim of this study is to investigate the effect of economic and financial development (FD) on environmental degradation (ED) for a sample of 12 selected small island developing states for the pe...

Hypericum sampsonii is an important medicinal plant used in Vietnam to treat many diseases such as backache, burns, diarrhea, and swelling. In order to study the chemical constituents in the aerial...

Vietnamese patients (106) tentatively diagnosed with encephalomyopathy were screened for the presence of 15 common point mutations in mitochondria using PCR-RFLP. The screened mutations include A3243G, T3271C and T3291C for Mitochondrial Encephalopathy, Lactic Acidosis and Stroke-like episodes (MELAS); A8344G and T8356C for Myoclonus Epilepsy and Rag-Red Fibers (MERRF); G11778A, G3460A and T14484C for Leber's Hereditary Optic Neuropathy (LHON); T8993G/C and T9176G for Leigh syndrome; A1555G for deafness syndrome; G4298A, T10010C, T14728C and T14709C for neuromuscular syndrome. As a result, 6 cases of A3243G (5.7%) and 2 cases of T14727C (3.9%) were found. The 6 cases of A3243G mutation were heteroplasmic at different levels (4.23-80.85%). The T14727C change was discovered for the first time in the MTTE gene encoding for tRNA(Glu) and showed homoplasmy. The T14727C change was probably a mutation because it was further confirmed as vertically inherited from the mother and not the result of isolated polymorphism.

The authors report an effective and simple route to prepare gold nanoparticles/graphene hybrid via the way of chemical functionalization. First, graphene nanosheets were functionalized with 4-mercaptobenzonic acid via a direct Friedel-Crafts acylation reaction in a polyphosphoric acid/phosphorus pentoxide medium. Second, gold nanoparticles were prepared from the in situ reduction of gold (III) chloride trihydrate by sodium borohydride. Subsequently, gold nanoparticles were decorated on graphene surface via the well-developed Au-S chemistry. High-resolution transmission electron microscopy and atomic force microscopy were employed to investigate the distribution of gold nanoparticles on the surfaces of graphene nanosheets.

This article examines whether the presence of blacks and Hispanics has a negative impact on prices in a small urban housing market in the US. To alleviate estimation biases associated with unobserved neighborhood heterogeneity, we focus on housing price differences across micro-neighborhoods in the small and relatively homogeneous city of Kingston, New York, introduce GIS-based spatial amenity variables as controls, and account for clustered errors, neighborhood fixed effects, spatial errors and spatial lags. Our results, with the exception of the spatial error model, conform with the consensus reached primarily from studies of large cities that the presence of blacks in a neighborhood is associated with lower housing prices and that the impact of the presence of Hispanics is considerably weaker. The spatial error model yields weaker and statistically insignificant results for blacks, providing some evidence that price discounts in relatively black neighborhoods may be caused not by preferences for segreg...

This paper examines the dynamics of return and volatility spillovers across the REIT markets of Japan, Singapore, Hong Kong, Malaysia, Taiwan, Thailand, and South Korea from June 2006 to May 2011. The emerging markets offer lower returns than the developed markets but lower risk as well. The emerging REIT index outperformed the developed REIT index on a risk-adjusted basis. The analysis suggests that correlations among Asian REIT markets are relatively low, ranging from 0.14 to 0.42 over the full-sample period. The results further indicate that correlations among emerging REIT markets are lower than that among developed markets. However, correlations are non-constant over time and increased during the recent Global Financial Crisis. The results from the EGARCH models show that there is a strong tendency for REIT returns to transmit from developed markets (e.g., Japan and Singapore) to emerging REIT markets. In regard to volatility transmission, the mechanism appears to be multidirectional. (ProQuest: ... denotes formulae omitted.) Since their establishment in Japan in 2001, real estate investment trusts (REITs) have flourished rapidly across Asia. Asian REITs have become attractive investment vehicles for international funds seeking portfolio diversification (Newell, Liow, Ooi, and Zhu, 2005; Ooi, Newell, and Sing, 2006). As of July 2011, there were more than 95 listed REITs across Asia with a total market capitalization of U.S. $98.7 billion, accounting for 12% of the global REIT market and 5.1% of the global listed real estate securities market (Macquarie Equities Research, 2011). Apart from the success of REITs in the developed markets of Japan, Hong Kong, and Singapore, the last decade has also witnessed impressive growth of the emerging Asian REIT markets, which include Malaysia, Taiwan, Thailand, and South Korea, underpinned by impressive property developments and favorable demographic terms. Despite their growth prospects and increasing significance, investors still have little information and knowledge on these emerging Asian markets. Therefore, a comprehensive understanding of the interrelationships between the emerging and developed Asian REIT markets is crucial for the development of portfolio diversification, trading strategies, hedging, and risk management for investors. The body of literature on REIT markets in Asia has been thin and modest as compared to that on the United States and Australia. Studies on the performance of Asian REITs in investment portfolios and their correlations with other financial assets had been carried out within a regional context (Chiang, So, and Tang, 2008; Quek and Ong, 2008; Cheok, Sing, and Tsai, 2011; Ong, Ooi, and Kawaguichi, 2011) or for specific countries such as Japan (Kutsuna, Dimovski, and Brooks, 2008; Su, Huang, and Pai, 2010), Singapore (Sing and Ling, 2003), Hong Kong (Newell, Wu, Chau, and Wong, 2010), Malaysia (Newell, Ting, and Acheampong, 2002: Lee and Ting, 2009; Newell and Osmadi, 2009, 2010; Hwa and Wai, 2011), Taiwan (Lin, 2007; Lee, Kuo, Lee, and Lin, 2011), Thailand (Pham, 2011a), and South Korea (Pham, 2011b). Other studies have investigated the linkages in international real estate securities, including the Asia Pacific region (Garvey, Santry, and Stevenson, 2001; Liow, Ho, Ibrahim, and Chen, 2009). These studies, however, concentrate on the listed property companies rather than REITs. The only published paper that examined the volatility transmission of REIT returns in Asia is that of Li and Yung (2007), who investigated the interactions between the Pacific (Australia, Hong Kong, Japan, and Singapore) and the Atlantic REIT markets (U.K. and U.S.). In general, the findings from previous studies can be summarized as: (1) Asian REITs offer diversification benefits to investors as they have low correlations with other asset classes; (2) the correlation structures are non-constant over time, and (3) there are significant mean and volatility spillover effects from the U. …

Water-dispersible graphene nanosheets were achieved by a simple three-step process. First, pristine graphite was oxidized and exfoliated to obtain graphene oxide, which was further acylated with thionyl chloride to introduce acyl chloride groups on the surfaces. Second, graphene oxide was covalently functionalized with an environment-friendly reagent, namely, adenosine. Subsequently, adenosine-functionalized graphene oxide was reduced to obtain graphene nanosheets by using NaBH4 as a reducing agent. This approach facilitates graphene nanosheets that have a combination of stable aqueous dispersions and an electrical conductivity that are much better in comparison to graphene oxide, offering a great flexibility for further applications.

Water dispersibility of multiwalled carbon nanotubes (MWNTs) has been achieved by functionalisation of the MWNTs with sodium gluconate (SOGL). The chemical grafting of SOGL onto the surfaces of MWNTs was carried out by producing acyl chloride groups on the oxidised MWNTs, and then, anhydride bond was formed between the SOGL and functionalised MWNTs. In addition, we also studied the chemical stability of anhydride bond in acid solution, base solution and neutral water with pH values of 5, 9 and 7 respectively. On the other hand, boronic acid functionalised gold nanoparticles were prepared for the decoration of gold nanoparticles to yield novel hybrid nanostructures via the formation of boroester bonds. The resulting novel hybrid nanostructures were investigated in detail using various techniques, including Fourier transform infrared spectroscopy, UV visible spectroscopy, high resolution transmission electron microscopy, field emission scanning electron microscopy and X-ray photoelectron spe...

This study examines the development of REITs in Thailand over October 2003 – September 2010, analyses their risk and return characteristics, investigates the dynamic correlations between REITs and ...

This paper examines the risk and return characteristics of K-REITs and the correlation of Korean real estate investment trusts (K-REITs) to other asset classes and their diversification potential i...

Water-dispersible multi-walled carbon nanotubes (MWNTs) were successfully prepared by the chemical grafting of acylated MWNTs with adenosine. The MWNTs were first purified and oxidized in order to obtain carboxylic acid funcionalized MWNTs, which was further acylated with thionyl chloride to give acyl chloride bound MWNTs. Then, adenosine was grafted onto the surface of nanotubes by chemical functionalization via esterification or amidation reaction. Further, novel hybrid nanostructures were synthesized by reaction of hydroxyl groups between adenosine-functionalized MWNTs and boronic acid functionalized gold nanoparticles to form boronate ester linkages that anchor gold nanoparticles onto the external surface of functionalized nanotubes.

Studies of women and Information Technology (IT) in developing countries have primarily focused on the impacts of IT on women's employment opportunities and on their economic power. By contrast, here we examine the nature and quality of the jobs themselves in the context of the Vietnamese software industry. This article presents data from the first systematic survey of Vietnam's software workforce. Although the industry is relatively young, gender segregation in software work has already been firmly established. Women are concentrated in jobs that are considered to be less skilled than those of men, such as testing as opposed to programming and systems design. This, in turn, has led to a gender gap in pay and training, as well as posed career barriers for women. The case study illustrates how the long-standing interconnection of gender, skill, and technology still functions to men's advantage, as a result of which women remain marginalized in the course of technological design.

Life-cycle performance evaluation of structures relies heavily on the usability of measured data. Typically, measurements are utilized to update the state of knowledge about a structure. This usually leads to a system identification problem. Due to the ill-conditionedness of inverse problems, the actual value of the obtained data may be severely reduced. Selective sensitivity provides a methodology to improve the condition of the inverse problems by transforming the original (large) problem into a sequence of smaller ones. The paper discusses this concept and develops a novel alternative concept for the development of selectively sensitive excitations, which does not require precise knowledge of the system parameters.