1 Terracotta tiles are $1-$2.50 a square foot, or $100-$250 for 10x10 feet; European terracotta may cost more.  Natural stone tiles of marble, granite, slate or more start at $2 a square foot, or $200 for 10x10-feet, but costs climb rapidly for custom designs or special orders.
The term probiotic is derived from the Latin preposition âpro,â which means âforâ and the Greek word âbioticâ meaning âbiosâ or âlifeâ. The concept that the gut flora can be modified and harmful microbes replaced with beneficial ones was first introduced in 1907 by a Russian scientist called Elie Metchnikoff.
The World Health Organization's (WHO) 2001 definition of probiotics is live micro-organisms which, when administered in adequate amounts, confer a health beneï¬t on the host. Following this definition, a working group convened by the FAO/WHO in May 2002 issued the âGuidelines for the Evaluation of Probiotics in Foodâ.