Facilitate formulation problem

ABSTRACT. Cyclodextrins are applied to facilitate formulation problems, to improve stability and bioavailability Following factors are determining whether or not cyclodextrins can be applied in oral pharmaceutical preparations ... 

The use of uncertainty analysis and probabilistic methods requires systematic and detailed formulation of the assessment problem. To facilitate this, a) risk assessors and risk managers should be given training in problem formulation, b) tools to assist appropriate problem formulation should be developed, and c) efforts should be made to develop generic problem formulations (including assessment scenarios, conceptual models, and standard datasets), which can be used as a starting point for assessments of particular pesticides. 

Excipients both typically contain water and are required to interact with it. The water associated with excipients can exist in various forms. Studies with different materials have shown that water can exist in association with excipients in at least four forms that may be termed free water, bound water, structural water, and water of crystallization. Water associated with a particular excipient may exist in more than one form (26). The type of water will govern how it is implicated in interactions between the excipient and the API or another excipient. The so-called free water is the form that is most frequently implicated in excipient interactions. Bound water is less easily available for interaction, and structural water is usually the least available one. Water of crystallization can be very tightly bound into the crystal structure however, there are some comparatively labile hydrates, e.g., dibasic calcium phosphate dihydrate (see above). If water of crystallization remains tightly bound within the crystal structure, it is unlikely to participate in an excipient interaction. However, any material that is in equilibrium with air above 0% RH will have some free moisture associated with it. In reality, below about 20% RH, the amount of moisture will probably be insufficient to cause problems. However, if sufficient moisture is present (e.g., at a higher RH), it can facilitate the interaction between components of the formulation. 

A PF/SAP document was prepared in order to guide the implementation and interpretation of the overall sediment quality triad. Objectives in a PF/SAP are identical to that of a problem formulation following a traditional ERA approach (U.S. EPA, 1998). PF/SAP documents are often submitted for regulatory approval prior to any sample collection in order to facilitate dialogue between interested parties. Our experience suggests that this dialogue during the problem formulation... 

If the consequences of setting a standard will have important environmental, economic, or social consequences, we envisage an approach in which a social and economic analysis forms part of the overall decision in conjunction with the scientific analysis. The two activities come together in an MCDA that seeks to integrate all the factors that will deliver the required level of environmental protection at an acceptable economic and social cost. If that cost can be defined during problem formulation, this will greatly facilitate the process because it puts limits on what is, and is not, permissible. 

The task decomposition allows the problem-solving process to be largely decoupled between tasks and also facilitates reasoning about subtasks. An important principle is that tasks plan about and directly manipulate only their immediate subtasks. Recursive application of this principle is the key to integrated behavior of a formulation system as a whole. The task tree is built on dynamically, depending upon the specification at hand as the problem-solving process proceeds. This is different to the object hierarchy where the structure is fixed for a particular domain. 

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