Temporal response

A potential pitfall with stop-time experiments comes with temporal instability of responses. When a steady-state sustained response is observed with time, then a linear portion of the production of reporter can be found (see Figure 5.15b). However, if there is desensitization or any other process that makes the temporal responsiveness of the system change the area under the curve will not assume the linear character seen with sustained equilibrium reactions. For example, Figure 5.16 shows a case where the production of cyclic AMP with time is transient. Under these circumstances, the area under the curve does not assume linearity. Moreover, if the desensitization is linked to the strength of signal (i.e., becomes more prominent at higher stimulations) the dose-response relationship may be lost. Figure 5.16 shows a stop-time reaction dose-response curve to a temporally stable system and a temporally unstable system where the desensitization is linked to the... 

The main characteristics which determine the performance of a wavefront corrector are the number of actuators, actuator stroke and the temporal response. The number of actuators will determine the maximum Strehl ratio which can be obtained with the AO system. The price of a deformable mirror is directly related to the number of actuators. The actuator stroke should be enough to compensate wavefront errors when the seeing is moderately poor. This can be derived from the Noll formula with ao = 1.03. For example, on a 10m telescope with ro = 0.05m at 0.5 m, the rms wavefront error is 6.7 /xm. The deformable mirror stroke should be a factor of at least three times this. It should also include some margin for correction of errors introduced by the telescope itself. The required stroke is too large for most types of deformable mirror, and it is common practice to off-load the tip-tilt component of the wave-front error to a separate tip-tilt mirror. The Noll coefficient a2 = 0.134 and... 

BIOLOGIC SYSTEMS EXHIBIT THREE TYPES OF TEMPORAL RESPONSES TO A REGULATORY SIGNAL... 

Temporal response to changes in abundance of MeHg A slow rate of response to altered MeHg loading could increase the potential for interference by confounding factors, whereas a rapid response, coupled with high intraannual variability would hinder identification of multiyear trends Hours to days Hours to days... 

Richer, S, Devenport, J, and Lang, JC, 2007. LAST II Differential temporal responses of macular pigment optical density in patients with atrophic age-related macular degeneration to dietary supplementation with xanthophylls. Optometry 78, 213-219. 

Thus, the region 2100-1830 cm 1 can be covered. This allows us to monitor CO(v,J) by resonance absorption and various M(CO)n [n = 3-6] as a result of near coincidences between the CO laser lines and the carbonyl stretching vibrations of these species. The temporal response of the detection system is ca. 100 ns and is limited by the risetime of the InSb detector. Detection limits are approximately 10 5 torr for CO and M(CO)n. The principal limitation of our instrumentation is associated with the use of a molecular, gas discharge laser as an infrared source. The CO laser is line tuneable laser lines have widths of ca. lO cm 1 and are spaced 3-4 cm 1 apart. Thus, spectra can only be recorded point-by-point, with an effective resolution of ca. 4 cm 1. As a result, band maxima (e.g. in the carbonyl stretching... 

The fabrication and characterization of a fiber optic pH sensor based on evanescent wave absorption was presented by Lee63. The unclad portion of a multi-mode optical fibre was coated with the sol-gel doped with pH sensitive dye. The sensitivity of the device increased when the multiple sol-gel coatings were used in the sensing region. The dynamic range and the temporal response of the sensor were investigated for two different dyes -bromocresol purple and bromocresol green. 

The spin Hamiltonian also forms the theoretical basis for describing the temporal response of the spin system to a pulse sequence and/or mechanical manipulations of the sample via calculations of the evolution of the density matrix. Computer... 

Bouwmans (1992 see also Bouwmans et al., 1997) used a particle tracking technique in a RANS flow field to estimate trajectories of neutral and buoyant additions, to construct Poincare sections of additions crossing specific horizontal cross-sectional planes, to predict probabilities of surfacing for buoyant additions, and to mimic the temporal response of conductivity probes. 

In this scheme, M <1 and K equilibrium constants. Direct binding experiments have confirmed the generality of this scheme for nicotinic receptors. Thus, distinct conformational states govern the different temporal responses that ensue upon addition of a ligand to the nicotinic receptor. No direct energy input or covalent modification of the receptor channel is required. 

Cunningham, J.J., W.M. Kemp, M.R. Lewis, and J.C. Stevenson. 1984. Temporal responses of the macrophyte Potamogeton perfoliatus L., and its associated autotrophic community to atrazine exposure in estuarine microcosms. Estuaries 7(4B) 519-530. 

Temporal Responses Within Algae Seconds to Weeks... 

It may be that temporal responses to environmental pressures occur in tandem at both the short and long terms, but further investigations are needed to confirm such... 

Figure 12.25. Wavelength dependence in the temporal response of a single-photon avalanche photodiode.

Equations (4.15)—(4.17) and subsequent theoretical expressions for r(t) are the true anisotropy, which is defined here as the fluorescence response to an instantaneous light pulse when measured by an instrument with infinitely rapid temporal response. In a real experiment this is convoluted with the instrument response function, as discussed in a later section. 

Figure 3.6 The temporal response of a detector after a sudden illumination.

The other important parameters, analyte vapor pressure and binding constant, also provide other means of selectivity. All other things being equal, those analytes with a higher vapor pressure than TNT should be easier to detect, as larger amounts of the analyte can be sampled and collected onto and into the polymer film. A small vapor pressure is typically seen as a sensitivity limit. However, with the large amphfication this technique gives, differences in vapor pressure can lead to different temporal responses that provide an additional mechanism to obtain selectivity. 

Because the binding of TNT and DNT is dependent on the structure of the polymer film, using two different polymers in series can assist in further discriminating the two similar analytes. This device architecture is shown in Figure 12. Figure 13 illustrates this effect in comparing the temporal response of TNT vapor... 

Liquid fuel was seldom utilized in the previous ACC studies because it was not only difficult to actuate liquid-fuel injection at high frequencies, but the combustion delays associated with liquid-fuel atomization, droplet heating, vaporization, and burning processes made such a control extremely slow for fast-response in situ type controllers. As a result, the use of liquid fuel was confined to either steady injection process ]13] or upstream addition of prevaporized fuel ]4, 7] which limited the ACC flexibility associated with temporal responsiveness. The goal of this project is to make ACC more practical for propulsion systems by studying direct liquid-fueled ACC in a closed-loop controller setting. 

K. HooL M. B. Seasholtz, R. Saunders, and D. Schlicker, Incorporeaing Temporal Response FacU>r into Pattern Recognition Schemes for Gas Phase Sensor Arrays, Paper No. 510, The Pittsburgh Conference, Chicago, IL, 1994. 

The factors that influence the chemical resolution of sensors are well understood and are not discussed here. This section reviews the factors that control the temporal resolution of sensors to be used for eddy correlation. In the analysis of the design of chemical sensors to be used for eddy correlation it is instructive to consider the different components of chemical sensor systems separately to determine the influences that they have on the temporal response to variations in the atmospheric concentration of a trace constituent. Of course this analysis is an oversimplification because the total systems operate in a more complex fashion, but it is a useful exercise. 

Newton AP, Justice JB. Temporal response of microdialysis probes to local perfusion of dopamine and cocaine followed with one-minute sampling. Analytical Chemistry 1994, 66, 1468-1472. 

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