Niemann-Pick disease is not directly caused by an alteration in an amino acid but rather is a genetic disorder affecting the metabolism of sphingolipids. It's usually caused by mutations in the SMPD1 gene for Niemann-Pick disease types A and B, affecting the enzyme acid sphingomyelinase, or in the NPC1 or NPC2 genes for type C, affecting the intracellular transport of cholesterol and other lipids. The mutations impair the breakdown of lipids, leading to their accumulation in various body tissues. While it's not about a specific amino acid being affected, the genetic mutations can impact the structure and function of the enzymes involved, which are composed of amino acids.

Decorating polypropylene (PP), a versatile thermoplastic polymer, often requires specific techniques due to its low surface energy, which makes adhesion difficult. A common approach is to treat the surface to increase its energy, thereby improving adhesion. Techniques such as flame treatment, corona treatment, or plasma treatment are effective in preparing PP surfaces for decoration. After treatment, PP can be painted, printed on, or applied with adhesives more effectively. When painting, use paints specifically formulated for plastics or PP. For printing, digital or screen printing methods can yield good results, using inks designed for PP. Additionally, applying a primer designed for use on plastics before painting or printing can enhance the durability of the decoration. Always test the chosen decoration method on a small area first to ensure compatibility and desired outcome.

Oil grade, such as those defined by the Society of Automotive Engineers (SAE), refers to the viscosity of the oil, indicating how well it flows at specific temperatures. The grades are shown in a format like 5W-30, where the first number followed by 'W' (standing for winter) indicates the oil's flow at 0°F, and the second number indicates the viscosity at 212°F. A lower first number means the oil remains more fluid in cold temperatures, essential for cold starts, while a higher second number shows the oil can maintain its lubricating properties at high temperatures, crucial for engine protection. The right oil grade ensures optimal performance, fuel efficiency, and longevity of an engine. Choosing the correct grade is vital and should comply with the vehicle manufacturer's recommendations.