Effective duration

It is possible to overcome some of the drawbacks of traditional duration by using OAS analysis to derive a bond s effective duration. As will be discussed in chapter l4, effective duration is based on approximate duration. Following Fabozzi (1997), approximate duration is derived using equation (11.13). 

P = the estimated price of the bond if the yield falls by Arm P = the estimated price of the bond if the yield rises by Arm Arm = the change in the yield of the bond 

Effective duration recognizes that yield changes may effect the future cash flow of a bond and so its price. For bonds with embedded options the difference between traditional duration and effective duration can be significant. The effective duration of a callable bond, for example, is sometimes half its traditional duration. As noted in chapter l4, for mortgage-backed securities, the difference is sometimes greater still. 

Effective duration may be calculated using the binomial model and equation (11.13), as follows  

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The time of effect duration (TED) is a ftmction of the elimination half-life. Two special cases are most important, the 50% effect bisection time (TED50) and the duration of 90% of the effect (TED90). 

D = Dnorm Cl/Clnorm D = Dnorm Fl/2norm/Fl/2 The administration interval could be selected based on standard peak and trough concentrations or from effect duration time (TED50, TED90). If the dose is reduced, a loading dose (Dload = Cpeak Vd = Dnorm) must be administered to obtain an immediate effect. If Dnorm = const. 

Plasma Type Ionization Effect (%) Duration of Ionization Effect (min)... 

The biomass is not effective throughout the whole cycle therefore, the process time (tP) is therefore the effective duration (tE) with respect to heterotrophic growth and endogenous respiration (Artan, 2001). 

Attention is also drawn to the fact that there are some other elements not included in the traditional assessment factor of 10 including adequacy of the database, nature of the effect, duration of exposure, route-to-route extrapolation, and considerations of extra-sensitive subpopulations such as children, the elderly, and patients under medical treatment. 

Oral methadone is about one half as potent as parenteral. Oral administration results in a delay of onset, a lower peak, and an increased duration of analgesic effect. Duration of effect increases with repeated use because of cumulative effects. 

Drug Onset of effect Peak effect Duration of effect Elimination ty ... 

Methadone 15-70 2-12 days Long effect duration in repeated doses. Should be dosed considering the long half-life. Risk of abuse... 

Isoproterenol is administered almost exclusively by inhalation from metered-dose inhalers or from nebulizers. The response to inhaled isoproterenol and other inhaled adrenomimetics is instantaneous. The action of isoproterenol is short-lived, although an objective measurement of pulmonary function has shown an effective duration of up to 3 hours. When it is administered by inhalation, the cardiac effects of isoproterenol are relatively mild, although in some cases a substantial increase in heart rate occurs. 

Glucocorticoid preparations differ with respect to relative anti-inflammatory and mineralocorticoid effect, duration of action, cost, and dosage forms available (Table 39-1), and these factors should be taken into account in selecting the drug to be used. 

The problem consists in finding the motion of the gas and the distribution of density, pressure and other parameters after an elapsed time which is large compared to the effective duration of the pressure, r. 

At low count rates the relative uncertainty of the pulser peak area in 1-day measurements remains below 10 3. At counting losses of 30% and at acquisition times of 1 h the relative uncertainty of the counting time does not exceed 1%. To cover the possible influence of systematic effects on the effective duration of the effective acquisition time originating in different counting conditions, a 1% uncertainty is included in the uncertainty budget at count rates exceeding 5000 s1. 

Fast Burnout A character under the influence of a drag with this benefit suffers side effects for a lesser period of time than normal. Side effects have their duration cut by 2/3 when suffered by a character under the influence of a drag with this benefit. For example, a drag with a side effect duration of 12 hours would be reduced to 4 hours. 

Test System Somatic/ Germinal NO. Persons Needed to Detect Effect Period from Exposure to Effect Duration of Test Effect ... 

To extend the usefulness of the model to permit a description of chemical reactions, we must introduce another parameter, the effective duration of a collision. The rectangular well or central force models do this automatically by permitting molecular interaction over a range of distances. However, they are both more complex than the hard sphere model. We can rescue the hard sphere model by specifying a parameter era, the effective diameter for chemical interaction, while keeping hard sphere core diameter. When the centers of two identical molecules are a distance effective reaction volume is 7r([Pg.155]

Cycloplegic Agent Commonly Used Concentration (%) Onset of Maximum Cycloplegic Effect Duration of Cycloplegic Effect Relative Residual Accommodation... 

Preanalytical variables fall under two categories—those that are controllable and those that are not. Those that can be controlled have short-lived effects. Duration of the other factors is much longer. Standardization of specimen collection practices minimizes the variables that cause changes in test values within one day or from one day to another and thereby reduces the difficulty in interpretation of values (see Chapter 2). However, in many healthcare facilities, standardization is not always possible. Thus one must understand the influences of both controllable and uncontrollable variables on the composition of body fluids. 

Unlike the majority of controlled-, sustained-, or extended-release systems in use, the extent of response in the lungs will be limited by intrinsic clearance mechanisms [110]. It will be surprising, but not unwelcome, if any deposited dosage form can extend the effective duration of action much beyond a day. Twenty-four hours would, in fact, be a significant achievement. 

How long these symptoms persist is determined by the Duration. Like Onset, Duration times can vary greatly. Duration not only determines how long symptoms persist, but also the persistence of some Damage effects. Duration should also be determined secretly by the GM when determining Onset time. 

Use of low-molecular stabilizers has essential shortage - protective effect duration time under working conditions, as they are quickly consmned at ultraviolet irradiation, washed out from the polymer and they are lightly volatile products. 

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