This property partially explains the "tears of wine" phenomenon. When wine is swirled in a glass, ethanol evaporates quickly from the thin film of wine on the wall of the glass. As the wines ethanol content decreases, its surface tension increases and the thin film "beads up" and runs down the glass in channels rather than as a smooth sheet. Flammability
An ethanol–water solution will catch fire if heated above a temperature called its flash point and an ignition source is then applied to it. For 20% alcohol by mass (about 25% by volume), this will occur at about 25 °C (77 °F). The flash point of pure ethanol is 13 °C (55 °F), but may be influenced very slightly by atmospheric composition such as pressure and humidity. Ethanol mixtures can ignite below average room temperature. Ethanol is considered a flammable liquid (Class 3 Hazardous Material) in concentrations above 2.35% by mass (3.0% by volume; 6 proof). Dishes using burning alcohol for culinary effects are called flambé. Natural occurrence
Ethanol is a byproduct of the metabolic process of yeast. As such, ethanol will be present in any yeast habitat. Ethanol can commonly be found in overripe fruit. Ethanol produced by symbiotic yeast can be found in bertam palm blossoms. Although some animal species, such as the pentailed treeshrew, exhibit ethanol-seeking behaviors, most show no interest or avoidance of food sources containing ethanol. Ethanol is also produced during the germination of many plants as a result of natural anaerobiosis.
Delayed pressure urticaria is known as one of the more painful subsets of physical urticaria due to formed hives being deep-seated and appearing after 4–6 hours. Causes
Due to the delayed appearance of wheals, plausible causes are hard to establish; the natural course and/or clinical pattern is variable and inconclusive. Treatment
It was noted that although antihistamines and anti-inflammatory drugs such as, colchicine, sulphasalazine, dapsone, and topical steroid are advocated for in the treatment of DPU, most if not all are unsatisfactory in relieving symptoms. Even a second generation antihistamine, ketotifen, was unable to efficiently and satisfactorily relieve symptoms of DPU


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