Descriptive feedback

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In contrast, by giving descriptive feedback, parents specify what about the child that has caught the parent s positive attention. "I enjoy watching the way you make friends laugh with your sense of humor." From this parental reflection, the child comes away with more appreciation for the funny part of who he or she is. 

Rudd21 has presented an adaptation of this method that covers systems involving feedback. Its development here is beyond the scope of this book. The reader should consult reference 21 for a description of this method. 

A final observation is in order the quantitative application of the equilibrium thermodynamical formalism to living systems and especially to ecosystems is generally inadequate since they are complex in their organisation, involving many interactions and feedback loops, several hierarchical levels may have to be considered, and the sources and types of energy involved can be multiple. Furthermore, they are out-of-equilibrium open flow systems and need to be maintained in such condition since equilibrium is death. Leaving aside very simple cases, in the present state of the art we are, therefore, limited to general semiquantitative statements or descriptions (e.g. ecosystem narratives ). 

The ar tide is organized as follows. We will begin with a discussion of the various possibilities of dynamical description, clarify what is meant by nonlinear quantum dynamics , discuss its connection to nonlinear classical dynamics, and then study two experimentally relevant examples of quantum nonlinearity - (i) the existence of chaos in quantum dynamical systems far from the classical regime, and (ii) real-time quantum feedback control. 

Originally ASTRA was developed on the base of existing models that have been converted into a dynamic formulation feasible for implementation in system dynamics and allowing for closure of the feedbacks between the models. Among these models have been the macroeconomic model, ESCOT (Schade et al., 2002) and the classical four-stage transport model, SCENES (ME P, 2000). The ASTRA model then runs scenarios for the period 1990 until 2030 using the first 12 years for calibration of the model. Data for calibration stem from various sources, with the bulk of data coming from the EUROSTAT (2005) and the OECD online databases (OECD, 2005). A detailed description of ASTRA is provided by Schade (2005). 

Aiming at a computer-based description of cellular metabolism, we briefly summarize some characteristic rate equations associated with competitive and allosteric regulation. Starting with irreversible Michaelis Menten kinetics, the most common types of feedback inhibition are depicted in Fig. 9. Allowing all possible associations between the enzyme and the inhibitor shown in Fig. 9, the total enzyme concentration Er can be expressed as... 

The development lab can benefit from valuable objective data to detect method shortcomings and to identify gaps in the method development process. The feedback on method performance should be discussed regularly. During the monitoring a number of key performance indicators are recorded and filled out in feedback sheets by the application labs (stability and operational labs) each time the method is applied. The method feedback sheet is sent together with the method description to the application labs at transfer. An example of such a feedback sheet is shown in Figure 22. 

A description of the carbonate compensation feedback system and its hypothesized roie in reguiating atmospheric CO2 ieveis is provided in the suppiementai information for Chapter 15.6 that is avaiiabie at http //elsevierdirect.eom/companions/9780120885305. 

The emphasis of the current research is on molecular structure of oligomeric fractions leached from quality cured, industrial resins. However, the potential for applications in quality control should not be overlooked. Chromatography analysis provides positive feedback capable of molecular descriptions of extent of cure actually achieved. Oligomeric distributions coupled to kinetic reaction analysis allows for detailed estimates of crosslink architecture within the resin (7). 

Another dimension of complexity must be layered on top of this description the demand for these forms of data is growing as drug hunter teams become increasingly reliant on ADME/Tox feedback during the course of their lead optimization programs. Naturally, this growing demand for data is a welcome trend, as it indicates broader opportunity for impact, but of course increased demand exacerbates the complexity of the process. 

Note that the employed definition of a system contains an important asymmetry between the system and the external world. The system s description includes the influence of the external forces on the system, but not the reverse, the influence of the system on the outside world. From a mathematical viewpoint the equations that describe the system s behavior contain the external forces, but the latter have to be taken from information outside the model. As will been shown, the specific hierarchy between system and outside world can often (but not always) be justified based on the respective strength of the interactions. Take the system of the earth. Solar radiation is a very strong driving force for the earth, but the back-radiation from the earth to the sun is so tiny that nobody would want to include it as a feedback mechanism in a radiation model of the sun. 

LOGICAL DESCRIPTION, ANALYSIS, AND SYNTHESIS OF BIOLOGICAL AND OTHER NETWORKS COMPRISING FEEDBACK LOOPS... 

Most systems involve several interconnected feedback loops. Such systems cannot be analyzed seriously without a proper formalism, but their detailed description using differential equations is often too heavy. For these reasons we (as many others before) turned to a logical (or Boolean) description, that is, a description in which variables and functions can take only a limited number of values, typically two (1 and 0). Section II is an updated description of a logical method ( kinetic logic ) whose essential aspects were first presented by Thomas and Thomas and Van Ham.2 A less detailed version of this part can be found in Thomas.3 The present paper puts special emphasis on the fact that for each system the Boolean trajectories and final states can be obtained analytically (i.e.,... 

But real systems are usually not simple feedback loops. In a virus such as bacteriophage the decision to kill the infected bacterial cell or to establish a symbiotic association with it depends on complex interactions involving a number of interconnected feedback loops. Such systems (and even simpler ones) would need a formal description in view of their complexity but as a matter of fact this complexity is such that the classical methods are much too heavy. This was a reason for trying a logical description, that is, a description using variables and functions which can take only a limited number of values—typically two (1 and 0). 

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