Milestones in dosimetry for nuclear medicine therapy.

Nuclear Medicine therapy has reached a critical juncture with an unprecedented number of patients being treated and an extensive list of new radiopharmaceuticals under development. Since the early applications of these treatments dosimetry has played a vital role in their development, in both aiding optimisation and enhancing safety and efficacy. To inform the future direction of this field, it is useful to reflect on the scientific and technological advances that have occurred since those early uses. In this review, we explore how dosimetry has evolved over the years and discuss why such initiatives were conceived and the importance of maintaining standards within our practise. Specific milestones and landmark publications are highlighted and a thematic review and significant outcomes during each decade are presented

Analysis of the accuracy and convergence of equation-free projection to a slow manifold

In [C.W. Gear, T.J. Kaper, I.G. Kevrekidis, and A. Zagaris, Projecting to a Slow Manifold: Singularly Perturbed Systems and Legacy Codes, SIAM J. Appl. Dyn. Syst. 4 (2005) 711-732], we developed a class of iterative algorithms within the context of equation-free methods to approximate low-dimensional, attracting, slow manifolds in systems of differential equations with multiple time scales. For user-specified values of a finite number of the observables, the m-th member of the class of algorithms (m = 0, 1, ...) finds iteratively an approximation of the appropriate zero of the (m+1)-st time derivative of the remaining variables and uses this root to approximate the location of the point on the slow manifold corresponding to these values of the observables. This article is the first of two articles in which the accuracy and convergence of the iterative algorithms are analyzed. Here, we work directly with explicit fast--slow systems, in which there is an explicit small parameter, epsilon, measuring the separation of time scales. We show that, for each m = 0, 1, ..., the fixed point of the iterative algorithm approximates the slow manifold up to and including terms of O(epsilon^m). Moreover, for each m, we identify explicitly the conditions under which the m-th iterative algorithm converges to this fixed point. Finally, we show that when the iteration is unstable (or converges slowly) it may be stabilized (or its convergence may be accelerated) by application of the Recursive Projection Method. Alternatively, the Newton-Krylov Generalized Minimal Residual Method may be used. In the subsequent article, we will consider the accuracy and convergence of the iterative algorithms for a broader class of systems-in which there need not be an explicit small parameter-to which the algorithms also apply

Influenza, a general review of recent developments

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The design of decentralised controllers for large scale systems

Bibliography:leaves 203-205.Decentralised control schemes are becoming more common in industry as the advantages of decentralised control become more apparent. These advantages include fewer tuning parameters than centralised controllers, the simplification and cost reduction of hardware requirements and greater reliability. In addition the application of decentralised controller design to large scale systems allows established CAD methods to be implemented easily and efficiently. When the control engineer designs a distributed controller the system is divided up into a number of subsystems and a controller designed for each subsystem. The controllers are designed independently for each subsystem ignoring any interaction that may occur between the different subsystems. In terms of the input-output representation of the system this means that the matrix representing the controller will be in a block diagonal form. In general the interactions between the different subsystems will not be negligible. In some cases the interactions will be such that stabilising the individual subsystems will not be sufficient to stabilise the system as a whole. Stability theorems are required to enable the designer to check if the decentralised controller that he has designed will in fact stabilise the system as a whole. Such stability theorems have been devised although at present they are too conservative. However even with such theorems available the designer must still select the subsystems to be controlled in such a way as to satisfy the conditions laid down for stability. The stability theories usually are based on a particular matrix structure. If the matrix representing the system possesses a structure detailed by the stability theorem in question then, subject to various conditions, the system as a whole will be stable under decentralised control. In this thesis a number of different matrix structures are considered that give information as to the stability of the closed loop system. Methods are developed that allow the designer to rearrange the matrix in such a way as to obtain a particular structure, if this is possible

High spatial resolution observations of CUDSS14A: a SCUBA-selected ultraluminous galaxy at high redshift

The definitive version is available at www.blackwell-synergy.com '. Copyright Blackwell Publishing DOI : 10.1046/j.1365-8711.2000.03822.xWe present a high-resolutionmillimetre interferometric image of the brightest SCUBA- selected galaxy from the Canada-UK deep SCUBA survey (CUDSS). We make a very clear detection at 1.3 mm, but fail to resolve any structure in the source.Peer reviewe

Enhanced thermal performance of garments embedded with encapsulated phase change material

The thermal storage and insulation properties of garments enhanced with phase change material (PCM) will be investigated using a finite difference procedure. A diver dry suit embedded with micro-encapsulated PCM will be shown to enhance thermal protection under extreme temperature conditions. Under conditions of high body heat production a garment embedded with Macro-encapsulated PCM is shown to absorb excess heat while maintaining a relatively constant temperature

Effect of Ankle Taping on Dynamic Balance and Perception of Stability

Purpose: The purpose of this study was to examine the actual and perceived effect of taping on dynamic stability. Methods: 21 physically active subjects [12 females (age = 20.33 ± 1.44 years, height = 165 ± 0.05 cm, mass = 68.76 ± 12.69 kg), and 9 males (age = 21.33 ± 1.66 years, height = 180 ± 0.10 cm, mass = 86.54 ± 9.46 kg)] participated in this study. Dynamic stability and perception of stability were assessed barefoot and with the ankle taped. The taped ankle condition used a standard preventive tape application including two anchors, three stirrups, close downs, horseshoes, two heel locks per side and two figures of eight. The Biodex Balance System SD was used to measure medial-lateral and anterior-posterior stability. Dynamic balance was assessed in a single leg stance during three 20-second trials at stability level 4. A 30-second rest period was provided between trials. Perception of stability was assessed using a 4-point Likert scale (1 = very unstable, 2 = unstable, 3 = stable, 4 = very stable) after each test session. Independent variables were counter-balanced to minimize the effects of fatigue associated with the testing procedures. A Repeated measures ANOVA was used to analyze the difference between barefoot and ankle tape for medial-lateral and anterior-posterior dynamic stability indices and perception of stability. All tests of significance were carried out at an alpha level = 0.05. The Bonferroni post hoc test was used for all paired comparisons. Results: Significant differences were not found for medial-lateral stability (Barefoot = 1.24 ± 0.63, Taped = 1.21 ± 0.72) nor anterior-posterior stability (Barefoot = 1.70 ± 1.07, Taped = 1.50 ± 0.89). Significant differences were found for perception of stability (Barefoot = 2.57 ± 0.60, Taped = 3.32 ± 0.67, p = 0.000). Conclusions: The use of ankle taping had no influence on dynamic stability measures in this study. Ankle taping did cause an increased perception of stability suggesting that ankle taping may have more of a placebo effect in uninjured ankles