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Most organic solvents are colorless liquids, usually stored in sealed containers. In manycases, their identification depends on the appropriate description on the container to prevent mishan-dling or mixing with other materials. Although modern laboratories rely heavily on identificationtechnologies, such as digitized inventories and spectroscopic methods (e.g., NMR or FTIR), there maybe situations where these cannot be used due to technical failure, lack of equipment, or time. An ex-ample of a portable and cost-effective solution to this problem is an electrochemical sensor. However,these are often limited to electrochemical impedance spectroscopy (EIS) or voltammetry methods. Toaddress this problem, we present a novel modular electrochemical sensor for solvent identificationthat can be used with either an EIS-enabled potentiostat/galvanostat or a simple multimeter. A novelmethod of fabricating and using a sensor consisting of a thin-film coating of an organic substance ona stainless-steel electrode substrate is presented. The differences in the solubility of the thin film indifferent solvents are used to distinguish between common organic solvents such as water, ethanol,and tetrahydrofuran.

Electrochromism encompasses reversible changes of material’s optical properties (color, opacity) under the influence of an external electric current or applied voltage. The effect has been known for decades, but its importance continues to grow due to the rapid development of smart systems and the accompanying demand to build devices that consume less power. Most commercial electrochromic devices (ECDs) require sophisticated chemicals and advanced material preparation techniques. Also, the demonstration of electrochromism in chemistry classes mainly uses expensive WO3films, intrinsically conductive polymers, and/or optically transparent electrodes (OTEs). The aim of this article is to present a simple and fast educational method to build ECDs from household materials without the need for OTEs: unsharpened kitchen knives are used as electrodes, curcumin from turmeric is used as the electrochromic dye, and baking soda is used as the electrolyte. The laboratory experiments presented will help students gain a deeper understanding of the fundamentals of electrochemistry (electrolysis, pH change) and electrochromism (in our case, color changes due to pH-induced keto-enol tautomerism of curcumin).

Humans are frequently exposed to environmental hepatotoxins, which can lead to liver failure. Biosensors may be the best candidate for the detection of hepatotoxins because of their high sensitivity and specificity, convenience, time-saving, low cost, and extremely low detection limit. To investigate suitability of HepG2 cells for biosensor use, different methods of adhesion on stainless steel surfaces were investigated, with three groups of experiments performed in vitro. Cytotoxicity assays, which include the resazurin assay, the neutral red assay (NR), and the Coomassie Brilliant Blue (CBB) assay, were used to determine the viability of HepG2 cells exposed to various concentrations of aflatoxin B1 (AFB1) and isoniazid (INH) in parallel. The viability of the HepG2 cells on the stainless steel surface was quantitatively and qualitatively examined with different microscopy techniques. A simple cell-based electrochemical biosensor was developed by evaluating the viability of the HepG2 cells on the stainless steel surface when exposed to various concentrations of AFB1 and INH by using electrochemical impedance spectroscopy (EIS). The results showed that HepG2 cells can adhere to the metal surface and could be used as part of the biosensor to determine simple hepatotoxic samples

Aim To characterise the clinical and histological features of MPL-mutated essential thrombocythaemia (ET). Patients and methods Bone marrow biopsies of 175 patients with ET were centrally reviewed according to the 2016 WHO classification, including 42 cases with MPL mutation, 98 JAK2V617F-mutated and 35 CALR-mutated. Clinical and histological features were compared among the three genotypes included in the current 2016 WHO classification and among the different types of MPL mutations. Results Patients with MPL-mutated ET were significantly older than those with the other genotypes. Haematological values at diagnosis were similar among MPL-mutated and CALR-mutated ET, with both genotypes showing higher platelet counts and lower haemoglobin values than ET with JAK2V617F genotype. In the bone marrow, the median number of megakaryocytes was higher in MPL and CALR than in JAK2V617F genotype (16, 19 and 14 megakaryocytes per x20 power field, respectively, p=0.004). Histological features of prefibrotic myelofibrosis were rarely observed in MPL genotype, whereas sinusoidal hyperplasia, dense clusters of megakaryocytes and reticulin fibrosis were more frequent in CALR-mutated ET, with 11% of such cases fulfilling WHO 2016 histological criteria of prefibrotic myelofibrosis. With a median follow-up of 3.5 years, no significant differences were seen among genotypes regarding survival, vascular complications or myelofibrotic transformation. There were no significant differences in the clinical data or in the histological characteristics depending on the type of MPL mutation. ConclusionMPL and CALR ET genotypes share clinical and histological characteristics. In contrast to CALR genotype, features of prefibrotic myelofibrosis are uncommon in MPL-mutated ET.

Energies 10(4), 498 (2017). doi:10.3390/en10040498 special issue: "Special issue "Wireless power transfer 2016" / special issue editor: Hongjian Sun, guest editor", Published by MDPI, Basel