Animal Models in Peritoneal Dialysis

Over the last decades peritoneal dialysis (PD) has become a successful and widely used treatment for endstage  renal disease patients worldwide. Together with the increasing number of uremic patients successfully  treated with PD has grown an interest in physiological, pathophysiological and clinical aspects of this  therapeutic method. This article provides an overview of the current status on animal models used in studying  the histology and physiology of the peritoneum, as well as the process of peritoneal dialysis itself. We  discuss species of experimental animals, methods of peritoneal access, sampling for histology, different  techniques and methodologies, and complications of experimental models of PD.

Hadron cancer therapy complex employing non-scaling FFAG accelerator and fixed field gantry design

Non-scaling FFAG rings for cancer hadron therapy offer reduced physical aperture and large dynamic aperture as compared with scaling FFAGs. The variation of tune with energy implies the crossing of resonances during acceleration. Our design avoids intrinsic resonances, although imperfection resonances must be, and can be, crossed. We consider a system of three non-scaling FFAG rings for cancer therapy with 250 MeV protons and 400 MeV/u carbon ions. Hadrons are accelerated in a common RFQ and linear accelerator, and injected into the FFAG rings at .. .. . H+/C6+ ions are accelerated in the two smaller/larger rings to 31 and 250 MeV/68.8 and 400 MeV/u kinetic energy, respectively. The lattices consist of doublet cells with a straight section for RF cavities. The gantry with triplet cells accepts the whole required momentum range at fixed field. This unique design uses either high temperature super-conductors or super-conducting magnets reducing gantry size and weight. Elements with variable field at beginning and at end set the extracted beam at the correct position for a range of energies

Overcoming a fast transverse instability by means of octupole-induced tune spread in the Relativistic Heavy Ion Collider

During the Relativistic Heavy Ion Collider commissioning in 2001 a fast transverse instability was observed on the ramp. In general this could be counteracted with increased chromaticity, resulting in Landau damping. However this method could not be applied around transition energy where chromaticities have to change sign. So octupoles were used near transition energy to create transverse Landau damping and avoid the transverse instability, emittance blowup, and beam loss. This paper describes the considerations that led to the present scheme, as well as experimental results

A standard FODO lattice with adjustable momentum compaction

An existing lattice made of identical FODO cells can be modified to have adjustable momentum compaction. The modified lattice consists of repeating superperiods of four FODO cells where every two cells have different horizontal phase advance. In existing FODO cell rings an additional quad bus is required for every two consecutive cells. This allows tuning of the momentum compaction or {gamma}{sub t} could be an imaginary number. A drawback of this modification is relatively large values of the dispersion function (two or three times larger than in the regular FODO cell design)

An Integrated Circuit for Signal Processing of the AMS RICH Photmultipliers Tubes

An analog integrated circuit has been designed, in a BiCMOS 0.8 micron technology, for the feasability study of the signal processing of the AMS RICH photomultiplier tubes. This low power, three channel gated integrator includes its own gate and no external analog delay is requiered. It processes PMT pulses over a dynamic range of more than 100. A logic output that indicates whether the analog charge has to be considered is provided. This gated integrator is used with a compact DSP based acquisition system in a 132 channels RICH prototype. The charge calibration of each channel is carried out using a LED. The pedestal measurement is performed on activation of a dedicated input. The noise contribution study of the input RC network and amplifiers is presented.Comment: IEEE symp. on Nucl. Sci. and Med. Imaging, Toront