pulse code modulation
pulse code modulation (PCM) A technique used by
codecs to convert an analog signal into a digital bit stream. The amplitude (usually) of the analog signal is sampled (8000 samples per second for voice-quality telephone lines with 4000 Hz bandwidth), and a digital code is selected to represent the sampled value. The digital code is transmitted to the receiving end, which uses it to generate an analog output signal. Encoding techniques may be used to reduce the amount of data that is transmitted between the sender and the receiver, based on known characteristics of the analog signal. For example,
mu-law (μ-law) encoding converts the analog signal to a digital code based on the logarithm of its value, rather than on a linear transformation.
Differential PCM (DPCM) transmits the difference between the current sample and the previous sample. DPCM assumes that the difference requires fewer bits than the signal amplitude.
Delta (Δ) PCM is a version of DPCM in which a single bit is used for each sample, representing a signal change of plus or minus one unit. A constant signal is represented as a series of plus or minus transitions.
Predictive PCM extrapolates from the previous few samples what the next sample should be, and transmits the difference between the actual value and the predicted value.
See also
modulation.
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Manufacturers stop UK supply of catgut sutures.
Newspaper article from: Biomedical Materials; 4/1/2001; 700+ words
; Manufacturers of catgut sutures have stopped supplying them to...made from bovine intestinal material. Catgut sutures have been used in surgery for...synthetic alternatives. Consequently, catgut sutures now constitute less than 10...
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Treatment of hyperlipemia by acupoint catgut-embedding in 34 cases.(Abstracts: The Journal of Traditional Chinese Medicine Abstracts September 2003)
Magazine article from: The Journal of Chinese Medicine; 2/1/2004; ; 700+ words
; ...hyperlipaemia were randomly divided into a catgut-embedding group (34 cases) and a medication...30 cases). Of the 34 cases in the catgut embedding group, 24 were male and 10...nephritic syndrome were excluded. For the catgut-embedding group, bilateral Zusanli...
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Seventy-two cases of sciatica treated by catgut point-embedding therapy.(Abstracts)
Magazine article from: The Journal of Chinese Medicine; 10/1/2007; ; 540 words
; ...into a treatment group which received catgut point-embedding therapy, and a control...subcutaneously along the cleavage lines, the catgut lengths (4 for the main points and 3...sensation was felt under the forceps. The catgut lengths were then gently lifted and pressed...
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FDA grants United States Surgical Corporation permission to market catgut sutures.
PR Newswire; 8/24/1989; 700+ words
; ...SURGICAL CORPORATION PERMISSION TO MARKET CATGUT SUTURES NORWALK, Conn., Aug. 24...reconsider its decision to down classify catgut sutures." In a letter to Johnson &...has granted USSC permission to market catgut sutures under the 5l0(k) process...
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My mother is allergic to cats. Recently she had her thyroid operated on, and the doctors sewed her throat with a thread they called 'catgut.' She had an allergic reaction to it. Was that because the thread was from a real cat?(Ask Doctor Cory)
Magazine article from: Child Life; 9/1/1996; ; 598 words
; ...her throat with a thread they called "catgut." She had an allergic reaction to it...Dhahran, Saudi Arabia Dear Karen: "Catgut" is an old term that describes the thread...to the thread used, but it was not `catgut' and had nothing to do with her allergy...
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Clinical observation in 46 cases of angina pectoris treated by the catgut-embedding therapy.(Abstracts: The Journal of Traditional Chinese Medicine Abstracts September 2003)(Brief article)
Magazine article from: The Journal of Chinese Medicine; 2/1/2004; ; 700+ words
; ...and yang deficiency of both the Heart and Kidney (1 case). Catgut suture was cut into pieces of 1-2.5 cm in length, and then...lidocaine was injected for local anaesthesia, the medicated catgut suture was threaded in the lumbar puncture needle and was embedded...
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 "Rocky Mountain News (Denver, CO)")
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TENNIS DELAYED - IT'S RAINING CATGUT AND DOGS ADVANTAGE, DELUGE? LEAD SLIM, EXPERTS SAY.(News)
Newspaper article from: Rocky Mountain News (Denver, CO); 10/7/2004; ; 700+ words
; Byline: Alexandra Obregon, Rocky Mountain News High school tennis players set to square off in the Region 4 tournament at Cherry Creek High School on Wednesday afternoon had to hold off for what has become a regular occurrence in the metro area this fall: rain. "We got here, and the clouds rolled
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Challenging Mayeda to take guts, catgut Cherry Creek senior is the player to beat in 5A singles tennis.(Rocky Preps)
Newspaper article from: Rocky Mountain News (Denver, CO); 8/17/2006; ; 700+ words
; Byline: Tracy Renck, Special to the News When talking to some of the top Class 5A boys high school tennis coaches, this much is clear: Doug Mayeda is the best player in the state. Mayeda is a senior this fall at Cherry Creek. A year ago, Mayeda won the coveted No. 1 singles state title by beating
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Fashions Conjure Thoughts Of Catwalk, Not Catgut
Newspaper article from: The Washington Post; 8/29/2007; ; 680 words
; Perhaps it's a response to performing on the highest-wattage stage in tennis. Or perhaps it's a reaction to Wimbledon's stringent dress code. Whatever the reason, the U.S. Open seems to bring out the plumage in female tennis players like no other tournament. And this year is no exception. Defending
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Fast-absorbing polyglactin 910 sutures decrease pain.(Obstetrics)
Magazine article from: OB GYN News; 11/15/2005; ; 700+ words
; ...with standard polyglactin 910 and chromic catgut. Patients repaired with fast-absorbing...Only 42% of women repaired with chromic catgut sutures and 56% with standard polyglactin...at 6 weeks. Just 27% in the chromic catgut cohort and 42% in the standard polyglactin...
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catgut
Book article from: The Columbia Encyclopedia, Sixth Edition
catgut or gut, cord made from the intestines of various animals (especially sheep...imported from Italy, are considered the best for musical instruments. Catgut is also used for stringing tennis rackets and for some surgical sutures.
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Suture
Book article from: How Products Are Made
...suture materials include silk, linen, and catgut, which is actually the dried and treated...making surgery much safer. Lister soaked catgut suture material in phenol making it sterile...spent over 10 years experimenting with catgut, to find a material that was supple...
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Novo Industri A/S
Book article from: International Directory of Company Histories
...autoclaving sheep guts produced a versatile surgical thread called Catgut. The popularity of this product kept Novo Facilities occupied...when new methods of suturing wounds supplanted the need for Catgut, production was abandoned. Novo introduced another product...
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string
Book article from: The Oxford Pocket Dictionary of Current English
...or attach to something. ∎ a piece of catgut or similar material interwoven with others to form the head of a sports racket. ∎ a length of catgut or wire on a musical instrument, producing a note by vibration...
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Novo Nordisk A/S
Book article from: International Directory of Company Histories
...autoclaving sheep guts produced a versatile surgical thread called Catgut. The popularity of this product kept Novo Facilities occupied...when new methods of suturing wounds supplanted the need for Catgut, production was abandoned. Producing Trypsin in World War...
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