signal

(redirected from Weak signals)
Also found in: Dictionary, Thesaurus, Legal, Financial, Encyclopedia.

sig·nal

(sig'năl),
1. Something that causes an action or conveys information.
2. A DNA template sequence that alters RNA polymerase transcription.
3. The end product observed when a specific sequence of DNA or RNA is deleted by some method.
4. The message transmitted on binding of an agonist to a receptor.

signal

(sĭg′nəl)
n.
Biology A physical entity, such as a chemical or an electromagnetic wave, that activates a cell receptor and elicits a specific response.
v. sig·naled, sig·naling, sig·nals or sig·nalled or sig·nalling
v.tr.
To cause an effect in (a cell) by the activation of a receptor, as by a neurotransmitter or hormone.

sig′nal·er, sig′nal·ler n.

signal

A measurable or recognisable indicator of an event or process.

signal

Medtalk A measurable or recognizable indicator of an event or process. See Magnetic resonance signal, Sexual body signal.

sig·nal

(sig'năl)
1. Something that causes an action.
2. A DNA template sequence that alters RNA polymerase transcription.
3. The end product observed when a specific sequence of DNA or RNA is deleted by some method.
4. Anything or action that communicates something.

signal

1. audible or visible indications to animals in behavioral conditioning. Many signals have had long-term use in the animal world and are used worldwide. Whoa and Getup, Heel and Sit are common examples. Getawayback is perhaps more colloquial. Many sheepdogs are trained to react to whistles and performing animals are usually trained to react to gestures with the hand.
2. in biochemical terminology relates to staging in reactions; see signal sequence.

signal peptidase
an integral membrane protein located on the luminal surface of the endoplasmic reticulum that cleaves the signal peptide and frees the protein for folding and export.
signal recognition particle (SRP)
a particle composed of six different proteins and one small (7S) RNA that binds to the signal peptide as it emerges from the ribosome, temporarily halting the synthesis of the protein while the complex is transported to the endoplasmic reticulum where the SRP recognizes and docks to a docking protein located on the cytoplasmic surface followed by the transfer of the ribosome to a ribosome receptor on the membrane; the SRP and its docking protein are released from the ribosome and translation resumes.
signal transduction proteins
proteins which may be a protein kinase, an ion channel forming protein (as in nerve cells), or a protein that undergoes some energy dependent change in which the energy is supplied by the hydrolysis of a higher energy compound such as guanosine triphosphate.
References in periodicals archive ?
The inductive scenarios that will be developed in the next phase will emerge from interactions among future impacts across multiple trends and weak signals.
Using a Wilson signal booster the Softrock crew was able to detect and amplify the weak signal, providing cellular coverage at the test site.
The weak signals scan identified more than 20 emerging forces that may alter our view of R&D's role in the future:
Radio receiving conditions change continually on portables and automotive systems, so an LNA is typically used to obtain better images from very weak signals.
ViaLogy's core competency incorporates rapidly and accurately detecting weak signals buried in high noise background and clutter.
The first five steps focus on directly improving the process of receiving, interpreting and acting on weak signals from the periphery.
Firing spontaneously and randomly, the fake neurons of such a bundle all receive inputs from the same weak signal source, and they send their individual outputs to a "summing center.
The external antenna/amplifier combination increases data rates for data users in shadowed or weak signal areas and helps reduce dropped calls and disconnects by increasing cellular signal quality and range.
Louis have now shown that an optimal level of external noise can indeed enhance weak signals traveling along individual sensory neurons in a crayfish.
Mercury5 is also equipped with a more sensitive receiver, even reading tags that have weak signals due to distance, obstruction or poor performance.
The high performance input buffer and 16 bit A/D converter core provide the high linearity and noise performance necessary to detect and isolate weak signals in the presence of large signals, blockers, and spectral clutter.
Researchers are now starting to explore potential applications of stochastic resonance in digital signal processing and for detecting weak signals.