Stepwise approaches

Function event trees are developed to represent the plant s response to each initiator. The function event tree is not an end product it is an intermediate step that provides a baseline of information and permits a stepwise approach to sorting out the complex relationships between potential initiating events and the response of the mitigating features. They structure plant respoases to accident conditions - possibly as time sequences. The transition labels of function event trees (usually along the top of the event tree) are analyzed to provide the probability of that function occurring or not occurring. 

As attractive as the transannular bridging of bis(thiolactones) to bicyclic bis(oxepane) frameworks is, our inability to convert the disulfide bridging product (see 25, Scheme 5) to a mmv-fused bre-vetoxin-type bis(oxepane) (see 28) necessitated the development of a modified, stepwise strategy. This new stepwise approach actually comprises two very effective methods for the construction of cyclic ethers the first of these is the intramolecular photo-induced coupling of dithioesters, and the second is the reductive cyclization of hydroxy ketones. We will first address the important features of both cyclization strategies, and then show how the combination of the two can provide an effective solution to the problem posed by trans-fused bis(oxepanes). 

Part A, dealing with the Fundamentals of Quantitative Chemical Analysis, has been extended to incorporate sections of basic theory which were originally spread around the body of the text. This has enabled a more logical development of theoretical concepts to be possible. Part B, concerned with errors, statistics, and sampling, has been extensively rewritten to cover modern approaches to sampling as well as the attendant difficulties in obtaining representative samples from bulk materials. The statistics has been restructured to provide a logical, stepwise approach to a subject which many people find difficult. 

In the early 1990s, Moore et al. reported the syntheses of a tremendous variety of meffl-connected PAMs [5 b, 36]. They recognized that the structural rigidity of systems like 8 could be useful in supramolecular chemistry. The convergent, stepwise approach of linear oligomeric phenylacetylene sequences developed in the Moore laboratory permitted absolute control over chain length, order of... 

Parmar, B., Miller, P.F., and Burt, R., Stepwise approaches for estimating the intakes of chemicals in food, Regul Toxicol. Pharmacol, 26, 44, 1997. 

TABLE 11-1. Classification of Severity and Stepwise Approach For Managing Asthma... 

The stepwise approach is intended to assist, not replace, the clinical decision making required to meet individual patient needs. 

Figure 18.40 The retrofit can be proceed in a stepwise approach. (From Asante NDK and Zhu XX, 1997, Trans IChemE, 75A 349, reproduced by permission of the Institution of Chemical Engineers.)...

Because the whole idea of a tiered approach of the kind outlined above is in its initial stages, it will have to be validated and discussed further and will in all probability need to be refined afterwards. The aim here is to introduce the idea of a stepwise approach to the assessment of the risk to re-entry workers. The outlined procedure should be used to calculate the dermal re-entry exposure for real examples of rather dermally toxic compounds in order to gain experience with the recommended procedure. 

The advantage of iterative strategies is based on the specific preparation of well defined structures and structurally perfect spacers of nanometer scale. This stepwise approach yields monodisperse material in contrast to other statistical routes. The use of the same reactants and the conversion of the same functional groups facilitates the synthetic effort compared with non-iterative methods. 

Quiquampoix H (1987) A stepwise approach to the understanding of extracellular enzyme activity in soil. I. Effect of electrostatic interactions on the conformation of a P-D-glucosidase adsorbed on different mineral surfaces. Biochimie 69 753-763... 

Common side effects of dopamine agonists are nausea, confusion, hallucinations, lightheadedness, lower-extremity edema, postural hypotension, sedation, and vivid dreams. Less common are compulsive behaviors, psychosis, and sleep attacks. Hallucinations and delusions can be managed using a stepwise approach (Table 55-4). When added to L-dopa, dopamine agonists may worsen dyskinesias. 

Stepwise Approach to Management of Drug-Induced Hallucinosis and Psychosis in Parkinson s Disease... 

Most treatment-resistant depressed patients have received inadequate therapy. Issues to be considered in patients who have not responded to treatment include the following (1) Is the diagnosis correct (2) Does the patient have a psychotic depression (3) Has the patient received an adequate dose and duration of treatment (4) Do adverse effects preclude adequate dosing (5) Has the patient been compliant with the prescribed regimen (6) Was treatment outcome measured adequately (7) Is there a coexisting or preexisting medical or psychiatric disorder (8) Was a stepwise approach to treatment used (9) Are there other factors that interfere with treatment ... 

A Stepwise Approach to Adjust Drug Dosages for Patients with Renal Insufficiency... 

Fig. 80-1 depicts the NAEPP stepwise approach for managing chronic asthma. Fig. 80-2 illustrates the recommended therapies for home treatment of acute asthma exacerbations. 

Quality can not be guaranteed. One can increase the probability that a care is good or better . If the different components in the structure and process are improved the probability of a better patient outcome is increased. Sometimes it is not possible to measure patient outcomes. Instead surrogate outcomes of the process performance can be used especially if there is evidences for a link to real patient outcomes. For improvement and assessing improvement Donobedian suggests a mix of approaches in the structure, process, outcome model. For improving clinical performance Donobedian also suggests a stepwise approach as described in Box 3.1. 

In order to show the inflation of q2, which results from the use of improper statistical methods, we have performed comparative studies involving stepwise regression and RR [68,70]. In these studies, comparative models were developed for the prediction of rat fat air and human blood air partitioning of chemicals. For the former, proper statistical methods yielded a model with a q2 value of 0.841, while the stepwise approach was associated with an inflated q2 of 0.934. Likewise, the rat fat air model derived using proper methods had a q2 value of 0.854, while the stepwise approach yielded a model with an inflated q2 of 0.955. 

The CDRH draft document (1997) actually sets forth a concise and stepwise approach to evaluating the potential immunotoxicity risks of devices and is likely to serve as a basis for approaches by other FDA centers. 

Table 3 Stepwise Approach to Developing a Dissolution Method...

Similarly, the structure of the nervous system is interwoven with its function. At all levels, from the microscopic highly branched nerve cell to the multiple connections between large brain regions that are visible to the naked eye, the structure of the nervous system is obviously designed to serve its chief purpose communication. As a result, it is difficult to talk about structure separately from function. Nevertheless, a divided, stepwise approach may help make these complicated matters easier for you to understand. 

Short-Term Treatment. In the acute phase of treatment, a stepwise approach is often warranted. The medication should be targeted at the most distressing symptom of narcolepsy first. This is almost invariably the sleep attacks and daytime drowsiness. 

Erdogan ME, Gulec S, Tutar E, Baskal N, Erdogan G (2003) A stepwise approach to the treatment of amiodarone-induced thyrotoxicosis. Thyroid 13 205-209... 

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