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Central 95% interval

Another size or an asymmetrical location of the reference interval may be more appropriate in particular cases. To prevent ambiguity, the definition of the interval should always be stated. The estimation of percentiles presented in the following sections is based on the conventional central 95% interval, but the techniques are easily adapted to other locations of the limits. [Pg.435]

BzzIntegra IGauss Based on the Gauss-Kronrod formulae. BzzIntegralGaussBF The interval is split into three subintervals. The lateral subintervals are very small and an interpolating polynomial based on Chebyshev points is adopted. The central interval is solved using the Gauss-Kronrod formulae. [Pg.41]

It is also frequently assumed that the free electron concentration is locally proportional to the center concentration. Referring to a Kroger diagram (Fig. 1) this means that the colorations occurred in the central interval. According to recent results 101 103 it seems likely that certain colorations may have occurred over broader ]1q ranges involving a zone where the free electron concentration was proportional to the square root of the center concentration. [Pg.347]

Method comparison between SIDA, radiobinding assay (A) or microbiological assay (B) for serum folates. The results are presented as Bland-Altman difference plots solid line represents the mean difference between the two methods. The SIDA method is used as the comparison method. Dashed lines represent the limits of agreement or 0.95 central intervals of the differences between the two methods (mean difference = 2 SD). A total of 46 serum samples were used in the analysis in A and 49 for the analysis in B. [Pg.441]

A reference interval, denoting the 95% central interval obtained for healthy individuals, must be determined. [Pg.466]

Disk Filters A disk filter is a vacuum filter consisting of a number of vertical disks attached at intervals on a continuously rotating horizontal hollow central shaft (Fig. 18-127). Rotation is by a gear drive. Each disk consists of 10 to 30 sectors of metal, plastic, or wood, ribbed on both sides to support a filter cloth and provide drainage via an outlet nipple into the central shaft. Each sector may be replaced individually. The filter medium is usually a cloth bag slipped over the sectors and sealed to the discharge nipple. For some heavy-duty applications on ores, stainless-steel screens may be used. [Pg.1717]

Nuremberg, Numbers I589-I6I5, 279-292 (1975)], is essentially a centrifugal pipet device. Size distributions are calculated from the measured solids concentrations of a series of samples withdrawn through a central drainage pillar at various time intervals. [Pg.1826]

The original optimization problem with five variables was, by choosing the liquid flow rate in section I by pressure-drop limitations and following Equations (35) and (36) to evaluate the switch time interval and the recycling flow rate, reduced to a two-variable optimization problem the choice of liquid flow rates in the two central sections. Table 9-5 summarizes the SMB operating conditions (and equivalent TMB conditions) used in the design of the 7 -711 plot. [Pg.247]

Command modules communicate with other modules through a local area network (LAN). Through this LAN, command modules receive information from the local control modules and store data. These data can be stored from a week to two years, depending on the recording interval and the number of points to be monitored. Unlike host-based systems, which use a central computer to interrogate each command module individually, the computer interface can tap into the network like any other command module. [Pg.466]

Type 2 - fI = fi t) is characterized by a saw-tooth-like pattern of peaks of various amplitudes, with the peaks appearing at almost regular intervals transition waves travel outward from a central focus to the boundary, with widely differing radii type-2 behavior typically appears for 3 < i/ < 8. [Pg.425]

The cause of this difficulty therefore resides within the counter itself. The difficulty is described by saying that the Geiger counter has a dead time, by which is meant the time interval after a pulse during which the counter cannot respond to a later pulse. This interval, which is usually well below 0.5 millisecond, limits the useful maximum counting rate of the detector. The cause of the dead time is the slowness with which the positive-ion space charge (2.5) leaves the central wire under the influence of the electric field. This reduction in observed counting rate is known as the coincidence loss. [Pg.52]

The behavior of the flow pattern in a parallel micro-channel is different from that in a single micro-channel. It was shown by Hetsroni et al. (2003b) that at the same value of heat flux, different flow regimes may be observed in different micro-channels, depending on the time interval. Moreover, at the same time interval different flow regimes may exist in each of the component micro-channels. In Fig. 2.33 two-phase steam-water flow in the central part of such a parallel system db = 100 pm is shown as the top view observed through a transparent cover. The... [Pg.49]

The axoneme consists of a cylinder of nine outer doublets of fused microtubules and a pair of discrete central microtubules (commonly referred to as the 9 + 2 arrangement of microtubules). The outer doublets each consist of a complete A-microtubule and an incomplete B-microtubule, the deficiency in the wall of the latter being made up by a sharing of wall material with the former. The tip of the axoneme contains the plus ends of all of the constituent microtubules. Two curved sidearms, composed of the MAP protein dynein, are attached at regular intervals to the A-microtubules of each fused outer doublet (Figures 1 and 2). [Pg.9]

Because EHD film thickness is determined by the viscosity of the fluid in the contact inlet [46], it is obvious that the viscosity of OMCTS remains at the bulk value down to approximately 0.1 m/s. However, below this speed the discretization of both central and minimum film thicknesses can be observed. The central film thickness begins to deviate from the theory at about 10 nm and the interval of the discretization is approximately 2 nm. If the molecular diameter of OMCTS that is about 1 nm is taken into account, it corresponds to approximately two molecular layers. [Pg.40]

Classic parameter estimation techniques involve using experimental data to estimate all parameters at once. This allows an estimate of central tendency and a confidence interval for each parameter, but it also allows determination of a matrix of covariances between parameters. To determine parameters and confidence intervals at some level, the requirements for data increase more than proportionally with the number of parameters in the model. Above some number of parameters, simultaneous estimation becomes impractical, and the experiments required to generate the data become impossible or unethical. For models at this level of complexity parameters and covariances can be estimated for each subsection of the model. This assumes that the covariance between parameters in different subsections is zero. This is unsatisfactory to some practitioners, and this (and the complexity of such models and the difficulty and cost of building them) has been a criticism of highly parameterized PBPK and PBPD models. An alternate view assumes that decisions will be made that should be informed by as much information about the system as possible, that the assumption of zero covariance between parameters in differ-... [Pg.543]

Figure 22.3 The drug dose-response model was augmented by nsing data for the comparator drug. Because the mechanism of the drugs was the same, this comprised additional data for the model. This enhanced the predictive power of the model, in a better estimate for central tendency (solid line compared with dotted line) bnt also in smaller confidence intervals. This is especially prononnced at the higher doses— precisely where data on the drug were sparse. See color plate. Figure 22.3 The drug dose-response model was augmented by nsing data for the comparator drug. Because the mechanism of the drugs was the same, this comprised additional data for the model. This enhanced the predictive power of the model, in a better estimate for central tendency (solid line compared with dotted line) bnt also in smaller confidence intervals. This is especially prononnced at the higher doses— precisely where data on the drug were sparse. See color plate.
Figure 39.4a represents schematically the intravenous administration of a dose D into a central compartment from which the amount of drug Xp is eliminated with a transfer constant kp. (The subscript p refers to plasma, which is most often used as the central compartment and which exchanges a substance with all other compartments.) We assume that mixing with blood of the dose D, which is rapidly injected into a vein, is almost instantaneous. By taking blood samples at regular time intervals one can determine the time course of the plasma concentration Cp in the central compartment. This is also illustrated in Fig. 39.4b. The initial concentration Cp(0) at the time of injection can be determined by extrapolation (as will be indicated below). The elimination pool is a hypothetical compartment in which the excreted drug is collected. At any time the amount excreted must be equal to the initial dose D minus the content of the plasma compartment Xp, hence ... Figure 39.4a represents schematically the intravenous administration of a dose D into a central compartment from which the amount of drug Xp is eliminated with a transfer constant kp. (The subscript p refers to plasma, which is most often used as the central compartment and which exchanges a substance with all other compartments.) We assume that mixing with blood of the dose D, which is rapidly injected into a vein, is almost instantaneous. By taking blood samples at regular time intervals one can determine the time course of the plasma concentration Cp in the central compartment. This is also illustrated in Fig. 39.4b. The initial concentration Cp(0) at the time of injection can be determined by extrapolation (as will be indicated below). The elimination pool is a hypothetical compartment in which the excreted drug is collected. At any time the amount excreted must be equal to the initial dose D minus the content of the plasma compartment Xp, hence ...
In the previous discussion of the one- and two-compartment models we have loaded the system with a single-dose D at time zero, and subsequently we observed its transient response until a steady state was reached. It has been shown that an analysis of the response in the central plasma compartment allows to estimate the transfer constants of the system. Once the transfer constants have been established, it is possible to study the behaviour of the model with different types of input functions. The case when the input is delivered at a constant rate during a certain time interval is of special importance. It applies when a drug is delivered by continuous intravenous infusion. We assume that an amount Z) of a drug is delivered during the time of infusion x at a constant rate (Fig. 39.10). The first part of the mass balance differential equation for this one-compartment open system, for times t between 0 and x, is given by ... [Pg.470]

Recent work shows that, in rodents, MDMA is metabolized, at least in part, to MDA, and that racemic MDMA is preferentially metabolized to 5 (+)MDA (Fitzgerald et al. 1987). The extent to which MDMA metabolites might contribute to the stimulus properties of MDMA is unknown at this time. Because 5 (-b)MDA is capable of producing AMPH-like stimulus effects, involvement of this metabolite might explain some of the different results reported for MDMA (particularly if different animal species and various presession injection intervals were employed). In contrast, certain other potential metabolites of MDMA, such as 3-hydroxy-PMA, 4-hydroxy-MMA, 3,4-dihydroxy-AMPH (a-tnethyldopamine), N-methyl-3-hydroxy-PMA, N-methyl-4-hydroxy-MMA, N-methyl-3,4-dihydroxy-AMPH (N-methyl-a-methyldopamine) do not produce AMPH-like stimulus effects, but may be capable of producing other, distinct types of central activity or may somehow interfere with potential AMPH-like effects. [Pg.59]

Domperidone minimally crosses the BBB it acts in the CTZ which lies outside of the BBB. As such, domperidone is less likely to cause the centrally-mediated adverse effects seen with metoclopramide and has an estimated overall incidence of 5% to 10%.1,30 However, domperidone has been associated with prolonged QT intervals, cardiac arrhythmias, and sudden death.31 It should not be used for patients with underlying long QT interval or for those on other medications that prolong the QT interval. Both metoclopramide and domperidone can cause hyperprolactinemia, galactorrhea, and gynecomastia. [Pg.301]

BUN, blood urea nitrogen CBC, complete blood cell count CNS, central nervous system CYP, cytochrome P-450 isoenzyme LFT, liver function test MAO, monoamine oxidase QTc, Q-T interval corrected for heart rate SCr, serum creatinine TMP-SMX, trimethoprim-sulfamethoxazole. [Pg.1183]


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See also in sourсe #XX -- [ Pg.434 , Pg.435 ]




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