Novel FFAG gantry and transport line designs for charged particle therapy

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.This thesis describes the design of novel magnetic lattices for the transport line and gantry of a charged particle therapy complex. The designs use non-scaling Fixed Field Alternating Gradient (ns-FFAG) magnets and were made as part of the PAMELA project. The main contributions in this thesis are the near-perfect FFAG dispersion suppression design process and the designs of the transport line and the gantry lattices. The primary challenge when designing an FFAG gantry is that particles with different momenta take up different lateral positions within the magnets. This is called dispersion and causes problems at three points: the entrance to the gantry, which must be rotated without distortion of the beam; at the end of the gantry where reduced dispersion is required for entry to the scanning system; and a third of the way through the gantry, where a switch in curvature of the magnets is required. Due to their non-linear fields, dispersion suppression in conventional FFAGs is never perfect. However, as this thesis shows, a solution can be found through manipulation of the field components, meaning near-perfect dispersion suppression can be achieved using ns-FFAG magnets (although at a cost of irregular optics). The design process for an FFAG dispersion suppressor shown in this thesis is a novel solution to a previously unsolved problem. Other challenges in the gantry lattice design, such as height and the control of the optics, are tackled and a final gantry design presented and discussed. The starting point for the transport line is a straight FFAG lattice design. This is optimised and matched to a 45o bend. Fixed field solutions to the problem of extracting to the treatment room are discussed, but a time variable field solution is decided on for practical and patient safety reasons. A matching scheme into the gantry room is then designed and presented

A Non-Scaling FFAG Gantry Design for the PAMELA Project

A gantry is re­quired for the PAMELA pro­ject using non-scal­ing Fixed Field Al­ter­nat­ing Gra­di­ent (NS-FFAG) mag­nets. The NS-FFAG prin­ci­ple of­fers the pos­si­bil­i­ty of a gantry much small­er, lighter and cheap­er than con­ven­tion­al de­signs, with the added abil­i­ty to ac­cept a wide range of fast chang­ing en­er­gies. This paper will build on pre­vi­ous work to in­ves­ti­gate a de­sign which could be used for the PAMELA pro­ject

Reversal of cardiac dysfunction by selective ET-A receptor antagonism

1. The effectiveness of a selective endothelin receptor-A (ET-A) antagonist, A-127722 (approximately 10 mg kg-1 day-1 as 200 mg kg-1 powdered food), to reverse existing cardiac remodelling and prevent further remodelling was tested in deoxycorticosterone acetate (DOCA)-salt hypertensive rats. 2. Uninephrectomised rats (UNX) administered DOCA (25mg every 4th day sc) and 1% NaCl in drinking water for 28 days developed hypertension (systolic BP: UNX 128 6, DOCA-salt 182 5* mmHg; *P<0.05 vs UNX), left ventricular hypertrophy (UNX 1.99 0.06, DOCA-salt 3.30 0.08* mg/kg body wt), decreased left ventricular internal diameter (UNX 6.69 0.18, DOCA-salt 5.51 0.37* mm), an increased left ventricular monocyte/macrophage infiltration together with an increased interstitial collagen from 2.7 0.3 to 11.7 1.3%, increased passive diastolic stiffness (UNX 21.1 0.5, DOCA-salt 30.1 1.3*), prolongation of the action potential duration at 20% and 90% of repolarization (APD20 - UNX 6.8 1.1, DOCA-salt 10.1 1.5* msec; APD90 - UNX 34.4 3.5, DOCA-salt 64.3 10.4* msec) and vascular dysfunction (2.6 fold decrease in maximal contractile response to noradrenaline, 3.5 fold decrease in maximal relaxation response to acetylcholine). 3. Administration of A-127722 for 14 days starting 14 days after surgery attenuated the increases in systolic blood pressure (150 6** mmHg, **P<0.05 vs DOCA-salt), left ventricular wet weight (2.65 0.06** mg/kg body wt) and internal diameter (6.39 0.31** mm), prevented left ventricular monocyte/macrophage accumulation, attenuated the increased left ventricular interstitial collagen (7.6 1.3%**), reversed the increased passive diastolic stiffness (22.1 1.2**), attenuated the action potential duration prolongation (APD20 - 7.6 1.4**, APD90 - 41.5 6.9** msec) and normalized changes in vascular function. 4. ET-A receptor antagonism both reverses and prevents the cardiac and vascular remodelling in DOCA-salt hypertension and improves cardiovascular function

Academic Integrity Pledges -- Acculturating Students to Integrity within Canadian Higher Education

Academic integrity, and its associated values, are an essential aspect of cultures that provide a foundation for conduct and behaviour of all members within higher education. Establishing such cultures support the quality of student learning as well as their ethical deportment within their programs of study. The merits of acculturating students within academic integrity has implications for their performance and commitment to similar conduct and behaviours in their chosen professional fields as positive, ethical, and caring professionals benefitting all who receive their care and service. Creating and sustaining such learning cultures requires a multifaceted approach and an understanding and appreciation for the complexity of nurturing such environments.  Academic integrity pledges situated across the learning trajectory at meaningful times during students' developmental paths, serve as one strategy that can be effective to academic integrity efforts.  How one School of Health Sciences has approached and realized academic integrity pledges are discussed, and may serve as an example for others.  The successes and opportunities for future development are outlined and reviewed

Developing Prevention-Oriented Discipline Codes of Conduct

A detailed analysis of prevention-oriented discipline in education