modulation


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modulation

 [mod″u-la´shun]
the normal capacity of cell adaptability to its environment.
antigenic modulation the alteration of antigenic determinants in a living cell surface membrane following interaction with antibody.

mod·u·la·tion

(mod'yū-lā'shŭn),
1. The functional and morphologic fluctuation of cells in response to changing environmental conditions.
2. Systematic variation in a characteristic (for example, frequency, amplitude) of a sustained oscillation to code additional information.
3. A change in the kinetics of an enzyme or metabolic pathway.
4. The regulation of the rate of translation of mRNA by a modulating codon.
[L. modulor, to measure off properly]

modulation

/mod·u·la·tion/ (mod″u-la´shun)
1. the act of tempering.
2. the normal capacity of cell adaptability to its environment.
3. embryologic induction in a specific region.

antigenic modulation  the alteration of antigenic determinants in a living cell surface membrane following interaction with antibody.
biochemical modulation  in combination chemotherapy, the use of a substance to modulate the negative side effects of the primary agent, increasing its effectiveness or allowing a higher dose to be used.

modulation

[mod′yəlā′shən]
an alteration in the magnitude or any variation in the duration of an electrical current. Modulation, which affects physiological responses to various waveforms, may be continuous, interrupted, pulsed, or surging.

modulation

The regulation of the rate at which a specific gene is transcribed.

mod·u·la·tion

(mod'yŭ-lā'shŭn)
1. The functional and morphologic fluctuation of cells in response to changing environmental conditions.
2. Systematic variation in a characteristic (e.g., frequency, amplitude) of a sustained oscillation to code additional information.
3. A change in the kinetics of an enzyme or metabolic pathway.
4. The regulation of the rate of translation of mRNA by a modulating codon.
5. Change in parameters of electrotherapy (e.g., frequency, amplitude).
[L. modulor, to measure off properly]

modulation

the capacity to regulate; widely used in biology, e.g. modulation of immune responses, food intake, etc.

antigenic modulation
the alteration of antigenic determinants in a living cell surface membrane following interaction with an antibody.
covalent modulation
activation or inactivation of enzymes, either by phosphorylation/dephosphorylation or by proteolytic cleavage. A major means of regulation of enzyme action by hormones.
References in periodicals archive ?
When a F1 case occurs, the effective reference and modulation process become that illustrated in Fig.
In this example, we can see that hylomorphism is a simple but powerful reduction, while modulation derives from a different ontology of matter, which we may call a philosophy of genesis, as opposed to the philosophy of hylomorphism.
In [11] author utilizes higher order cummulants for classification of PAM QAM and PSK of order 2 to 64 on AWGN channel and linear discriminant analysis (LDA) for classification of most fundamental modulation formats [12].
This modulation technique has been implemented and used in different works with success [7], [17].
4 is that, the modulation indices [DELTA]I, represented by colored vertical bars, become symmetrical, opposite to the highly asymmetric bars shown in Fig.
mod-M] represents the power consumption of the binary and M-ary modulation circuitry, [P.
It is "a major success for agriculture," he affirmed, adding that it may be possible to consider a voluntary modulation with obligatory national co-financing during the CAP health check', in the framework of a "dialogue" with the Parliament.
The modulation block can be implemented by various circuits for the given PLL loop filter.
The modulation concept was tested on the NIST cesium fountain clock, NIST-F1, and found to work so well that it has become the preferred mode of operation.
The RF2485 operates from a single 5V power supply and contains all of the required components to implement the modulation function including differential amplifiers for the baseband inputs, a 90 degree hybrid phase splitter, limiting LO amplifiers, two balanced mixers, a combining amplifier and an output RF amplifier which will drive a 50 ohm load.
This section describes in brief the underlying principles behind Amplitude Modulation, Frequency Modulation and Demodulation (Miller, 1996).
Up to now the maximum rate of modulation had been 2 billion bits per sercond (2 gigabits per second), that is, 2 billion light pulses a second.