Measures of response

Fig. 5.8. If a peak current value is recorded before wave transit time in the PVDF, the current is a measure of response in the thick, current mode. The observed currents are found to be approximately linear with stress.

The observation of dependent variable values (in functional experiments this is cellular response) as they happen (i.e., as the agonist or antagonist binds to the receptor and as the cell responds) is referred to as real time. In contrast, a response chosen at a single point in time is referred to as stop-time experimentation. There are certain experimental formats that must utilize stop-time measurement of responses since the preparation is irreparably altered by the process of measuring response. For example, measurement of gene activation through reporter molecules necessitates lysis of the cell. Therefore, only one... 

The complications of time become much more important in stop-time measurement of response, where a time is chosen to measure an amount of product from a biochemical reaction. Observing linearity in the production of response with respect to time allows determination that a steady state has been reached. 

There are patterns of dose-response curves that preclude Schild analysis. The model of simple competitive antagonism predicts parallel shifts of agonist dose-response curves with no diminution of maxima. If this is not observed it could be because the antagonism is not of the competitive type or some other factor is obscuring the competitive nature of the antagonism. The shapes of dose-response curves can prevent measurement of response-independent... 

We will first summarize the fluorescence and spectroscopic assays that have been developed for the fluorometer and then describe their applications using flow cytometry. We will summarize research which exemplifies the utility of simultaneous measurement of responses and shows how these methods have provided Information about the signal transduction pathways and activation in neutrophils. 

Determine success of the overall treatment plan by obtaining a thorough history of adverse events experienced with the previous chemotherapy/endocrine therapy treatment and objective measures of response to therapy. Assess effects on quality-of-life measures such as physical, psychological, and social function and well-being. 

Objective clinical measures of response include HR, blood pressure, and the DP as a measure of MVo2. 

Does this concept of a P-i diagram as a measure of response or damage work for complex structures, as well as simple ones ... 

The principle of using least squares may still be applicable in fitting the best curve, if the assumptions of normality, independence, and reasonably error-free measurement of response are valid. 

Although caffeine increases response speed in some visual attention taste, it is apparently not due to decreased distractibility or suppression of irrelevant responses (Kenemans and Verbaten 1998). Cognitive decline is evident during withdrawal from caffeine, primarily on measures of response time and sustained attention (Bernstein et al. 1998). The degree of habitual caffeine use is the strongest variable predicting the response to caffeine in a visual attention task (Loke and Meliska 1984). 

This section deals with published data related to short-term exposures of sensitive plants to ozone and the resulting responses. In most cases, the measure of response is a subjective estimate of visible injury. However, various growth measures have been reported in some research, and correlations between injury and growth measures are often possible (Table 11-3). These acute ozone effects have received sufficient study to permit the construction of preliminary models to relate time, ozone concentration, and plant response for a number of plant species. 

Finally, from the mean of replicate responses (y,) to the response itself (y,). This distance is a measure of the purely experimental uncertainty. If the measurement of response is precise, this distance should be small. 

The relative risk is calculated as a measure of response and is then used to calculate the excess lifetime cancer risk expressed as unit risk (associated with a lifetime exposure to 1 p,g/m ). 

Table 2.8. Typical issues addressed when designing a clinical trial protocol. The trial objectives should clearly define what questions the trial should answer. The study design section should contain comprehensive information detailing trial size, criteria used to choose the study population, and enrolment procedures. Description of intervention section should give the background to the intervention itself, its therapeutic rationale and how it is to be administered. Measurement of response should detail the data to be collected, how it will be collected and analysed. The organization and administration section should give full details of all the investigators, where the trial is being run, and its project management details...

Liebowitz et al. [1992] conducted a double-blind, placebo-controlled study of 74 subjects meeting DSM-lll-R (American Psychiatric Association 1987] criteria for social phobia with phenelzine, atenolol, or placebo for 8 weeks. Phenelzine daily doses were 60-100 mg. Phenelzine was found to be superior to both atenolol and placebo, and atenolol was not significantly different from placebo in measures of responsiveness of social phobia symptoms. 

The conceptual foundation of the system is first established by addressing such issues as its focus, dose-response relationships, measures of response, and the applicable risk management paradigm ... 

Different measures of response can be used in estimating risk. For example, risk could refer to the probability of occurrence (incidence) of a particular response or the probability that death will result. The probabilities of these two endpoints will rarely be the same, because some adverse effects will be cured by medical treatment or the receptor will die by some other means before death is caused by exposure to a hazardous substance. 

Measures of Radiation-Induced Responses. This Section discusses the measures of response from radiation exposure generally used in radiation protection and assessments of radiation risk in general terms. 

Second, the primary measure of stochastic response used in radiation protection and in most radiation risk assessments has been fatalities. In contrast, the measure of response for chemicals causing... 

Given the different approaches to dose-response assessment and the different measures of response normally used for radionuclides and chemicals that cause stochastic effects, estimates of responses from exposure to the two types of substances clearly are not equivalent, and the correspondence of the estimated frequency of responses to the frequency that might actually be experienced differs substantially. Specifically, if the results of experiments indicating chemical-induced stochastic responses in animals are assumed to be indicative of stochastic responses in humans, estimates of responses for chemicals could be considerably more conservative (pessimistic) than estimates for radionuclides. This difference is primarily the result of... 

Measures of Response from Exposure to Hazardous Substances... 

Development of a comprehensive and risk-based hazardous waste classification system requires assumptions about the measure or measures of response (adverse health effects) from exposure to radionuclides and hazardous chemicals that should be used in classifying waste. Possible measures of response discussed in Section 3.2.3 include fatalities, incidence, or some combination of the two, such as total detriment (ICRP, 1991). The following sections discuss the measures of response from exposure to hazardous subtances that... 

Measures of Response for Substances Causing Deterministic Responses. For purposes of health protection in routine exposure situations, incidence has been the primary measure of deterministic response for both radionuclides and hazardous chemicals. Fatalities also are of concern for substances that cause deterministic responses, but only at doses substantially above the thresholds for nonfatal responses. Given that the objective of standards for health protection is to prevent the occurrence of deterministic responses, incidence is not modified by any subjective factors that take into account, for example, the relative severity of different nonfatal responses with respect to a diminished quality of life. Judgments about the importance of deterministic responses are applied only in deciding which responses are sufficiently adverse to warrant consideration in setting protection standards. 

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