channel


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Related to channel: Chanel, YouTube Channel

channel

 [chan´el]
a passage, cut, or groove through which something can pass or flow across a solid structure.
calcium channel (calcium-sodium channel) a slow voltage-gated channel very permeable to calcium ions and slightly permeable to sodium ions, existing in three subtypes designated L, M, and N and located throughout the body; calcium channels are the main cause of action potentials in certain smooth muscles, and the N channels regulate neurotransmitter release.
fast channel a protein channel, such as a sodium channel, that becomes activated relatively quickly; a fast voltage-gated channel has a much lower activation potential than does the slow type. See also slow channel.
ligand-gated channel a protein channel that opens in response to the binding of a molecule (the ligand) to the protein, which causes a conformational change in the protein molecule. See also voltage-gated channel.
potassium channel a slow voltage-gated channel selective for the passage of potassium ions, found on the surface of a wide variety of cells, including nerve, muscle, and secretory cells; its functions include regulation of cell membrane excitability, regulation of repetitive low frequency firing in some neurons, and recovery of the nerve fiber membrane at the end of the action potential.
protein channel a watery pathway through the interstices of a protein molecule by which ions and small molecules can cross a membrane into or out of a cell by diffusion; protein channels play a vital role in depolarization and repolarization of nerve and muscle fibers, and may have physical characteristics such as shape or diameter that particularly attract certain ions.
slow channel a protein channel such as the calcium channel that is slow to become activated; a slow voltage-gated channel has a much higher activation potential than does the fast type. See also fast channel.
sodium channel a type of fast channel selective for the passage of sodium ions. Voltage-gated sodium channels are the main causes of depolarization and repolarization of nerve membranes during the action potential. In cardiac cells they produce phase 0 of the action potential.
voltage-gated channel a protein channel that can be opened or closed in response to changes in the electric potential across a cell membrane. See also ligand-gated channel.
water channel a channel in a cell membrane that permits passage of water molecules; chemical substances such as vasopressin cause the opening of new channels and increase permeability.

chan·nel

(chan'ĕl),
A furrow, gutter, or groovelike passageway.
See also: canal.
[L. canalis]

channel

(chăn′əl)
n.
1. A furrow, tube, or other groovelike passageway through which something flows.
2. An aqueous pathway through a protein molecule in a cell membrane that modulates the electrical potential across the membrane by controlling the passage of small inorganic ions into and out of the cell.
Drug slang A regional street term for a vein into which a drug is injected
Paranormal See Channeler, Energy channel
Physiology A multiprotein transmembrane complex—ionophore—with an amphipathic pore, which is hydrophobic on either side of the membrane and hydrophilic inside

channel 

A concept relating to the evidence that information about a particular feature of an image is transmitted and processed in the visual pathway approximately independently of information about other domains. The evidence was obtained from various experiments: matching, threshold elevation, after-effect, etc. Examples: the three channels of colour vision theory; the spatial frequency channels. See waterfall after-effect.

chan·nel

(chan'ĕl)
A furrow, gutter, or groovelike passageway.
[L. canalis]
References in periodicals archive ?
It goes without saying that a news channel that builds a credible brand will get better advertisements regardless of its TRPs-based profile.
Furthermore, Dish TV also has different channel packs grouping popular channels from broadcasters.
'The size of most NLNG vessels disturbs the water during movement, and any other ship that tries to make use of the Bonny channel whenever at the same time with an NLNG vessel is doing so at its own risk.
The penetration of HD channels across all markets continues to be an important driver of growth for SES.
where [QoS.sub.p] (X) is the Quality of IPTV service, according to the type of access network; h is the weighting factor of IPTV quality, dependent on the type of the access network for IPTV service; [I.sub.L] is the loss of IP packets; [I.sub.U] is the intensity of TV channel' s flows by the requests' intervals for that TV channel; [I.sub.J] is the IP packets' delay variation; [I.sub.D] is the IP packets' delay; [I.sub.B] is the network's bandwidth; [I.sub.I] is the parameter of IPTV service's quality; [W.sub.l], [W.sub.u], [W.sub.j], [W.sub.d], [W.sub.b], [W.sub.l] is the limits of the parameters of IPTV service's quality, depending on the type of the access network.
Faced as we are with a wealth of customer communications channels, it's very easy for them to get away from us.
Adding to this Anand Vardhan, Consultant and Channel Specialist at Business SALT said, “I have been part of Indian IT industry for the past 20 years and I feel that while the channel sales people have experience fulfilling market demand they tend to lack knowledge and experience in demand creation and channel programs and promotions which are addressed by Channel Success Essentials.”
THURSDAY: - Swimming, athletics, table tennis and sitting volleyball (Channel 4, 9.15am-12noon); athletics, wheelchair basketball and 5-a-side football (Channel 4, 12.05pm-1pm); athletics, wheelchair basketball, 5-a-side football and wheelchair tennis (Channel 4, 1pm-4.20pm); semifinals of the women's wheelchair basketball (More4, 4.20pm-5.25pm); swimming finals (Channel 4, 5.25pm-6.30pm); swimming and athletics (More4, 6.25pm-7.30pm); athletics, wheelchair basketball and wheelchair rugby (Channel 4, 7.30pm-10.30pm).
The change to themed movie channels makes it easier for viewers to find a movie that appeals to their mood or taste by simply going to the relevant themed channel.
The channels are broadcast on the three satellites Arabsat, Nilesat and Noorsat.
The average advertising rates of free-to-air satellite news and current affairs channels in the Arab world is $ 5,219 for a 30-seconds advertisement during peak time, said a new report titled "Satellite TV Advertising Rates in the Arab World 2010" released by the Arab Advisors Group.
The new HD networks will include: AMC HD, Animal Planet HD, BET HD, Biography Channel HD, Bravo HD, Cartoon Network HD, CMT HD, CNBC HD, CNN HD, CNN Headline News HD, Comedy Central HD, Disney XD HD, E!