Spontaneous responses

The methods to investigate the specificity of behaviorally active compounds include spontaneous responses of untrained animals and discrimination tests, where a discriminated stimulus is substituted by another closely related compound to detect the degree of generalization from one stimulus to another. In field studies, the first is the method of choice. 

Below 440°C the spontaneous response is moderate but does not reach a stable value immediately, indicating some additional contributions to P. Between 440-520°C Am increases multifold. In the upward "creeping" interval the return to the baseline is slow, indicating residual polarization. Above 550°C the Am response is fast again. 

Evaluators appeared to use these criteria to provide quick impressions of how essays were strange or likeable. Because these criteria were intuitive, spontaneous responses, they were not specific or particularly descriptive. In fact, evaluators seemed to draw upon past experiences reading and evaluating essays. In other words, placement readers may have found essays strange or likeable in relation to latent, subconscious memories of the hundreds, if not thousands, of placement essays they had evaluated. 

Quantitative risk assessment requires extrapolation from results of experimental assays conducted at high dose levels to predicted effects at lower dose levels which correspond to human exposures. The meaning of this high to low dose extrapolation within an animal species will be discussed, along with its inherent limitations. A number of commonly used mathematical models of dose-response necessary for this extrapolation, will be discussed. Other limitations in their ability to provide precise quantitative low dose risk estimates will also be discussed. These include the existence of thresholds incorporation of background, or spontaneous responses modification of the dose-response by pharmacokinetic processes. 

Figure 5.2 A model of the learning curve built into the CPE assay. During the acquisition phase, the level of the CR increased up to a maximum value at the third conditioning trial (A). This value is an indicator of the bee s ability to get conditioned properly, and can be compared according to the treatments. During the extinction phase, the level of the CR slowly decreased, back to the initial level of spontaneous response (B). This expresses the resistance of the bee s response to successive presentations of the unrewarded CS. Values in T1 and T5 are commonly used to compare responses of bees subjected to different treatments.

Combining spontaneous responses from different modaiities... 

Immunotherapy has been widely investigated for its potential use in cancer therapy. In both human and experimental animal neoplastic pathology spontaneous responses to tumor-associated antigens (TAAs) have been reported (Drake et al. 2005 Valmori et al. 2000). However, the expression of TAAs by tumor cells is... 

The fluctuation dissipation theorem relates the dissipative part of the response fiinction (x") to the correlation of fluctuations (A, for any system in themial equilibrium. The left-hand side describes the dissipative behaviour of a many-body system all or part of the work done by the external forces is irreversibly distributed mto the infinitely many degrees of freedom of the themial system. The correlation fiinction on the right-hand side describes the maimer m which a fluctuation arising spontaneously in a system in themial equilibrium, even in the absence of external forces, may dissipate in time. In the classical limit, the fluctuation dissipation theorem becomes / /., w) = w). 

The modem era of biochemistry and molecular biology has been shaped not least by the isolation and characterization of individual molecules. Recently, however, more and more polyfunctional macromolecular complexes are being discovered, including nonrandomly codistributed membrane-bound proteins [41], These are made up of several individual proteins, which can assemble spontaneously, possibly in the presence of a lipid membrane or an element of the cytoskeleton [42] which are themselves supramolecular complexes. Some of these complexes, e.g. snail haemocyanin [4o], are merely assembled from a very large number of identical subunits vimses are much larger and more elaborate and we are still some way from understanding the processes controlling the assembly of the wonderfully intricate and beautiful stmctures responsible for the iridescent colours of butterflies and moths [44]. 

Asthma is an extremely complex condition characterized by variable and reversible airways obstmction combiaed with nonspecific bronchial hypersensitivity (1 3). The cause of asthma, which is not always readily diagnosed (4), remains unknown. Days, if not weeks, ate needed to document the spontaneous reversal of the airways obstmction ia some patients. Asthmatics experience both an immediate hypersensitivity response and a delayed late-phase reaction, each mediated by a different pathway. Chronic asthma has come to be viewed as an inflammatory disease (5). The late-phase reaction plays a key role ia iaduciag and maintaining the inflammatory state which ia turn is thought to iaduce the bronchial hyperresponsiveness (6). The airways obstmction results from both contraction of airways smooth muscle and excessive bronchial edema. Edema, a characteristic of inflammatory states, is accompanied, ia this case, by the formation of a viscous mucus which can completely block the small airways. 

Ethanol is classified for medical purposes as a central nervous system (CNS) depressant. Its effects—that is, being drunk—resemble the human response to anesthetics. There is an initial excitability and increase in sociable behavior, but this results from depression of inhibition rather than from stimulation. At a blood alcohol concentration of 0.1% to 0.3%, motor coordination is affected, accompanied by loss of balance, slurred speech, and amnesia. When blood alcohol concentration rises to 0.3% to 0.4%, nausea and loss of consciousness occur. Above 0.6%, spontaneous respiration and cardiovascular regulation are affected, ultimately leading to death. The LD50 of ethanol is 10.6 g/kg (Chapter 1 Focus On). 

---