ppi

The initials PPI have several meanings:Italian People's PartyParallel Peripheral Interface - a connection for driving LCD displays on processors such as the BlackfinPatient and Public Involvement - Forums for English health trustsPayment protection insurancePersonal & Private Information (PPI Data)Philips Phonographische Industries - The original name for Philips RecordsPhonographic Performance (Ireland) LimitedPirate Party InternationalProducer Price Index, a metric used in economicsProductivity Point InternationalProgressive Policy InstituteProducer Price IndexPractical Process Improvement
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Pixels per inch (PPI) or pixel density is a measurement of the resolution of a computer display, related to the size of the display in inches and the total number of pixels in the horizontal and vertical directions. This measurement is often referred to as dots per inch, though that measurement more accurately refers to the resolution of a computer printer. PPI may also be used to describe the resolution of an image scanner or digital camera; in this context, it is synonymous with samples per inch.
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In chemistry, the anion, the salts, and the esters of pyrophosphoric acid are called pyrophosphates. The anion P2O74− is abbreviated PPi and is formed by the hydrolysis of ATP into AMP in cells.ATP → AMP + PPi For example, when a nucleotide is incorporated into a growing DNA or RNA strand by a polymerase, pyrophosphate (PPi) is released. Pyrophosphorolysis is the reverse of the polymerization reaction where pyrophosphate reacts with the 3'-nucleotidemonophosphate (NMP or dNMP), which is removed from the oligonucleotide to release the corresponding triphosphate (dNTP from DNA, or NTP from RNA).
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Index measuring changes in wholesale prices, published by the U.S. Bureau of Labor Statistics every month.

The Producer Price Index (PPI) is a family of indexes that measures the average change over time in selling prices received by domestic producers of goods and services. PPIs measure price change from the perspective of the seller. This contrasts with other measures, such as the Consumer Price Index (CPI), that measure price change from the purchaser's perspective. Sellers' and purchasers' prices may differ due to government subsidies, sales and excise taxes, and distribution costs.

Plane Position Indicator
  

Producer Price Index.
  

Prices Paid Index.