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cytosine (sīˈtōsēnˌ), organic base of the pyrimidine family. It was isolated from the nucleic acid of calf thymus tissue in 1894. A suggested structure for cytosine, published in 1903, was confirmed in the same year when that base was synthesized in the laboratory. Combined with the sugar ribose in glycosidic linkage, cytosine forms a derivative called cytidine (a nucleoside), which in turn can be phosphorylated with from one to three phosphoric acid groups, yielding the three nucleotides CMP (cytidine monophosphate), CDP (cytidine diphosphate), and CTP (cytidine triphosphate). Analogous nucleosides and nucleotides are formed from cytosine and deoxyribose. The nucleoside derivatives of cytosine perform important functions in cellular metabolism. CTP acts as a coenzyme in both carbohydrate and lipid metabolism; it can readily donate one of its phosphate groups to adenosine diphosphate (ADP) to form adenosine triphosphate (ATP), an extremely important intermediate in the transfer of chemical energy in living systems. CTP is the source of the cytidine found in ribonucleic acid (RNA) and deoxycytidine triphosphate (dCTP) is the source of the deoxycytidine in deoxyribonucleic acid (DNA). Thus cytosine is intimately involved in the preservation and transfer of genetic information.
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(1) See continuous data protection.

(2) (Charging Downstream Port) See USB power.

(3) (Certificate in Data Processing) An earlier award for the successful completion of an examination in hardware, software, systems analysis, programming, management and accounting, offered by the ICCP. See ICCP.

(4) (Cisco Discovery Protocol) A protocol used by Cisco bridges and routers to inform each other of their existence. It sends frames over the data link layer (Ethernet, frame relay, ATM, etc.) to a multicast address. The content of the CDP message is addresses that SNMP messages can be sent to.
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References in periodicals archive ?
The special night was attended by LFC legends and supporters alike, and marks over a decade that CDP has been supporting local charities in memory of their Founder, Joe Scanlon, raising over PS100,000 so far.
Implementation of Collection Development Policy (CDP) is therefore the wheel of progress required for successful execution of library services as well as providing reading materials to enhance educational objectives of the library.
The change in CDP's Outlook, in turn, reflected the Italian sovereign action taken on 31 August 2018 (see 'Fitch Revises Italy's Outlook to Negative; Affirms at 'BBB' at
The survey found that the CDP was delivering "significant value" for 80% of CDPIE members who had completed a deployment.
'We recognize the urgent call of organizations such as the CDP to act to prevent dangerous climate change and environmental damage.
CDP's General Manager of Commercial Imam Wahyudi said the CDP's participation aimed to introduce its integrated port development.
The CDP serves as a basis for the crafting of Local and Development Investment Plan and Annual Investment Plan.
This made US firms the biggest single national group and was similar to levels in 2016, according to CDP, which tracks companies' environmental performance and was formerly known as the Carbon Disclosure Project.
Through this restructuring of the family's assets, CDP America reinvested the proceeds into value-added properties throughout New York City, including the acquisition of 616 Bushwick Avenue, a 99-unit rental building located in Bushwick, Brooklyn.
Pinnacle Midstream LLC, a company that provides gas gathering and processing, crude gathering and transloading services, and SWD gathering and disposal services, has installed and started Sierra Grande CDP truck transloading facilities in Texas.
CDP, formerly known as The Carbon Disclosure Project, is the leading international not-for-profit organization assessing the work of companies worldwide in the area of climate change.