Bisphenol A (BPA) is used in a wide variety of consumer products owing to its beneficial properties of optical clarity, shatter resistance, and heat resistance. However, leached BPA has been shown to disturb the endocrine system and could cause cancer even at low concentrations, which has led to public concern. To reduce the toxic effects caused by BPA, it is important to monitor the BPA levels and its presence in products in a simple, rapid, and on-site manner. Here, we propose a new colorimetric strategy for the simple and rapid detection of BPA employing a DNA aptamer, a cationic surfactant, and gold nanoparticles (AuNPs). Using the developed system, the presence of BPA can be successfully determined based simply on a visually detectable color change from red to blue, triggered by aggregate formation of the AuNPs, which can be monitored even with the naked eye. Under the optimized conditions, this system could detect BPA with excellent selectivity and sensitivity, and its high performance was validated in the receipt obtained from local market and BPA-spiked tap water samples, ensuring its practical applicability. Moreover, the limit of the detection of the system was determined to be 97 nM, which is below the current tolerable daily intake level, demonstrating its suitability for toxicity assessment and on-site quality control in a more economical manner when compared with conventional methods.

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In this study, a three-stage-integrated process using the hydrogenic process (BioH), methanogenic process (BioCH), and a microbial fuel cell (MFC) was operated using molasses wastewater. The contribution of individual processes to chemical oxygen demand (COD) removal and energy production was evaluated. The three-stage integration system was operated at molasses of 20 g-COD L, and each process achieved hydrogen production rate of 1.1 ± 0.24 L-H L day, methane production rate of 311 ± 18.94 mL-CH L day, and production rate per electrode surface area of 10.8 ± 1.4 g m day. The three-stage integration system generated energy production of 32.32 kJ g-COD and achieved COD removal of 98 %. The contribution of BioH, BioCH, and the MFC reactor was 20.8, 72.2, and, 7.0 % of the total COD removal, and 18.7, 81.2, and 0.16 % of the total energy production, respectively. The continuous stirred-tank reactor BioH at HRT of 1 day, up-flow anaerobic sludge blanket BioCH at HRT of 2 days, and MFC reactor at HRT of 3 days were decided in 1:2:3 ratios of working volume under hydraulic retention time consideration. This integration system can be applied to various configurations depending on target wastewater inputs, and it is expected to enhance energy recovery and reduce environmental impact of the final effluent.

some machine learning algorithms for sex identification based on linear mandibular measurements derived from CT scans .