List of the 100 most densely populated cities in the United Kingdom, measured in people per square miles. 1  Portsmouth, Hampshire â 15,336. 2  London â 13,870. 3  Leicester, Leicestershire â 11,800. 4  Glasgow, Glasgow â 8,542. 5  Bristol, Bristol â 13,398. 6  Liverpool, Merseyside â 12,790. 7  Stoke-on-Trent, Staffordshire â 11,939.
In 1961 at the Wistar Institute in the US, Hayflick researched a phenomenon later called the Hayflick Limit, or the claim that normal human cells can only divide forty to sixty times before they cannot divide any further.
Lower explosive limit (LEL): The lowest concentration (percentage) of a gas or a vapor in air capable of producing a flash of fire in presence of an ignition source (arc, flame, heat).The term is considered by many safety professionals to be the same as the lower flammable limit (LFL).pper explosive limit (UEL): Highest concentration (percentage) of a gas or a vapor in air capable of producing a flash of fire in presence of an ignition source (arc, flame, heat). Concentrations higher than UFL or UEL are too rich to burn.