Mahidol University International College

Abstract: Wastewater containing pigments and/or dyes can cause serious water pollution problems in the form of reduced light penetration and photosynthesis, and the toxicity from heavy metals associated with pigments and/or dyes. Laboratory investigations, of the potential use of dried Spirodela polyrrhiza biomass as an adsorbent for the removal of the basic dye methylene blue from aqueous solution were conducted. A series of experiments were undertaken in an agitated batch adsorber to assess the effect of the system variables, i.e. sorbent dosage, pH, and contact time. The results showed that as the amount of the dried S. polyrrhiza increased, the percentage of dye sorption increased accordingly. At pH 2.0 the sorption of dye was not favorable, while the sorption at other pHs (3.0-11.0) was remarkable. There was no significant difference in the dye concentration remaining when the pH was increased from 3.0 to 11.0. The dye removal time was influenced by the initial dye concentration, and the process followed the first-order rate kinetics. The rate constants for intraparticle diffusion were 1.00 and 3.27 mg/g/min1/2 for 300 and 500 mg/l of dye, respectively.

Abstract: The Siam weed, Chromolaena odorata (L.) King & Robinson, Family Asteraceae, was found to be a new Pb hyperaccumulator by means of field surveys on Pb soil and hydroponic studies. Plants from field collection accumulated 1377 and 4236mgkg(-1) Pb in their shoots and roots, respectively, and could tolerate soil Pb concentrations up to 100000 mgkg(-1) with a translocation factor of 7.62. Very low concentrations of Cd and Zn were found in plants collected from the field. Under nutrient solution culture condition, C. odorata from the contaminated site (CS) and from non-contaminated site (NCS) grew normally with all three metals (Pb, Cd, Zn) supplied. However, the relative growth rates of all treated plants decreased with increased metal concentrations. The percentage uptakes of Pb, Cd, and Zn by C. odorata increased with increasing metal concentrations. Pb concentration in shoots and roots reached its highest values (1772.3 and 60655.7mgkg(-1), respectively) at a Pb supply level of 10mgl(-1). While the maximum concentrations of Cd (0.5mgl(-1)) in shoots and roots of C. odorata were 102.3 and 1440.9mgkg(-1), and the highest concentrations of Zn (20mgl(-1)) were 1876.0 and 7011.8mgkg(-1), respectively. The bioaccumulation coefficients of Pb and Cd were greater than 1000. These results confirm that C. odorata is a hyperaccumulator which grows rapidly, has substantial biomass, wide distribution and has a potential for the phytoremediation of metal contaminated soils.

Abstract: Triangle counting and enumeration has emerged as a basic tool in large-scale network analysis, fueling the development of algorithms that scale to massive graphs. Most of the existing algorithms, however, are designed for the distributed-memory setting or the external-memory setting, and cannot take full advantage of a multicore machine, whose capacity has grown to accommodate even the largest of real-world graphs.

Abstract: National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency,Pathumthani, ThailandChikungunya virus (CHIKV) has recently re-emerged causing millions of infections in coun-tries around the Indian Ocean. While CHIKV hasa broad host cell range and productively infectsa number of different cell types, macrophageshave been identified as a potential viral reser-voir serving to increase the duration of symp-toms. To date no CHIKV interacting protein hasbeen characterized and this study sought toidentify CHIKV binding proteins expressed ontarget cell membranes. Two-dimensional virusoverlay identified prohibitin (PHB) as a micro-glial cell expressed CHIKV binding protein. Co-localization, co-immunoprecipitation as well asantibody and siRNA mediated infection inhibi-tion studies all confirmed a role for PHB in me-diating internalization of CHIKV into microglialcells. PHB is the first identified CHIKV receptorprotein, and this study is evidence that PHBmay play a role in the internalization of multipleviruses. J. Med. Virol. 84:1757–1770,2012.

Abstract: A field survey of terrestrial plants growing on Bo Ngam lead mine area, Thailand, was conducted to identify species accumulating exceptionally high concentrations of lead. Plant and soil samples were collected from five areas. Lead concentrations in surface soil ranged from 325 to 142 400 mg/kg. The highest lead concentration in soil was found at the ore dressing plant area and lowest at a natural pond area. In different areas, the concentrations of lead in plants were different when comparing various study sites. A total of 48 plant species belonging to 14 families were collected from five sampling sites. Twenty-six plant species had lead concentrations more than 1000 mg/kg in their shoots. Three species ( Microstegium ciliatum , Polygala umbonata , Spermacoce mauritiana ) showed extremely high lead concentrations in their shoots (12 200–28 370 mg/kg) and roots (14 580–128 830 mg/kg).