Dr Laks says â[e]ven were the regression line to have a slope of zero, if the SD of the duct diameter increases as a function of time, then the upper limit of normal value would increase with age.â There is no indication that the variance increases with age.
PET, which stands for polyethylene terephthalate, is a form of polyester (just like the clothing fabric). It is extruded or molded into plastic bottles and containers for packaging foods and beverages, personal care products, and many other consumer products.ET is a polymer of ethylene glycol and terephthalic acid. Pellets of PET resin are heated to a molten liquid, which can be easily extruded or molded into almost any shape. PET was first synthesized in the U.S. during the mid-1940s by DuPont chemists searching for polymers that could be used to make new textile fibers.
Mylar is made out of polyethylene terephthalate, often abbreviated as PET. This is a less permeable plastic, but as you could see, but doesn't cling like the other plastic wraps you used. There are many factors that influence the way plastic wrap might keep something fresh.The thickness of the wrap will also change its permeability, and if two plastic wraps are made of the same polymer, the thicker wrap will be less permeable.ylar is made out of polyethylene terephthalate, often abbreviated as PET. This is a less permeable plastic, but as you could see, but doesn't cling like the other plastic wraps you used. There are many factors that influence the way plastic wrap might keep something fresh.