Hazardous waste management system design under population and environmental impact considerations

This paper presents a multi objective mixed integer location/routing model that aims to minimize transportation cost and risks for large-scale hazardous waste management systems (HWMSs). Risks induced by hazardous wastes (HWs) on both public and the environment are addressed. For this purpose, a new environmental impact definition is proposed that considers the environmentally vulnerable elements including water bodies, agricultural areas, coastal regions and forestlands located within a certain bandwidth around transportation routes. The solution procedure yields to Pareto optimal curve for two conflicting objectives. The conceptual model developed prior to mathematical formulation addresses waste-to-technology compatibility and HW processing residues to assure applicability of the model to real-life HWMSs. The suggested model was used in a case study targeting HWMS in Turkey. Based on the proposed solution, it was possible to identify not only the transportation routes but also a set of information on HW handling facilities including the types, locations, capacities, and investment/operational cost. The HWMS of this study can be utilized both by public authorities and private sector investors for planning purposes. © 2016 Elsevier Lt

MCT1-mediated transport of a toxic molecule is an effective strategy for targeting glycolytic tumors

There is increasing evidence that oncogenic transformation modifies the metabolic program of cells. A common alteration is the upregulation of glycolysis, and efforts to target glycolytic enzymes for anticancer therapy are under way. Here, we performed a genome-wide haploid genetic screen to identify resistance mechanisms to 3-bromopyruvate (3-BrPA), a drug candidate that inhibits glycolysis in a poorly understood fashion. We identified the SLC16A1 gene product, MCT1, as the main determinant of 3-BrPA sensitivity. MCT1 is necessary and sufficient for 3-BrPA uptake by cancer cells. Additionally, SLC16A1 mRNA levels are the best predictor of 3-BrPA sensitivity and are most elevated in glycolytic cancer cells. Furthermore, forced MCT1 expression in 3-BrPA–resistant cancer cells sensitizes tumor xenografts to 3-BrPA treatment in vivo. Our results identify a potential biomarker for 3-BrPA sensitivity and provide proof of concept that the selectivity of cancer-expressed transporters can be exploited for delivering toxic molecules to tumors.National Institutes of Health (U.S.) (NIH CA103866)Jane Coffin Childs Memorial Fund for Medical Research (Fellowship)National Science Foundation (U.S.) (Fellowship)Howard Hughes Medical Institute (Investigator

Is Adsorption an artefact in experimentation with triclosan?

This paper examines the effect of adsorption of Triclosan (TCS) onto labware on the results obtained during lab-scale experiments. Three sets of experiments were considered; two of them expose the problem in water or wastewater treatability studies and the other one in microbial susceptibility testings. In the former two sets, lab-scale systems; ozonation; and membrane filtration (NF/RO) that are commonly used in water or wastewater treatability studies were utilized and the distribution of TCS within the systems were followed. The ozonation labware tested was composed of a Pyrex reactor with plastic and glass tubings. The NF/RO system was composed of a stainless steel feed tank, a stainless steel membrane unit, stainless steel flanges, and stainless steel and plastic tubings. Ozonation system was operated without ozone gas, but air. Similarly, NF/RO system was without membrane in it. Both of the systems were rinsed with methanol before experiments to remove any possible earlier contamination. During the experiments, samples were taken at certain intervals and the change in TCS concentration in water was monitored. Results obtained with lab-scale ozonation system revealed that TCS adsorbed by the surface of plastic tubing is about 100 times greater than that of glass tubing. In NF/RO system, the higher the initial TCS concentration the higher the mass of TCS adsorbed by the membrane filtration system alone was evident. In the third set, microbial susceptibility testing was conducted on Staphylococcus aureus for TCS and the possible effect of adsorption of TCS onto the plastic labware was sought by comparing MIC and MBC values performed by serial dilutions in aqueous and methanol solutions. MIC and MBC values determined using TCS in methanol range from 0.06 to 16 mg/L, while the ones determined with TCS in water range from 0.25 to 128 mg/L. All the results obtained indicated that adsorption is a substantial phenomenon; in the event that it is not considered, obtained results might not reflect the truth. TCS was found to adsorb seriously on plastic but not on glass labwares. Therefore, before an experimental system that will employ TCS is designed, it is essential to consider the possible adsorption onto the experimental system components and to demonstrate that there is no adsorption of TCS onto labware