To use conventional ray tracing methods in Monte Carlo simulation of the collimator in a scintillation camera system can be time consuming. It is however necessary to take collimator interactions into account when simulating radionuclides emitting high-energy photons that can penetrate the septa in the collimator. In this work a statistical collimator algorithm, based on the Delta-Scattering metho

Osteoarthritis is complex in genetics, pathogenesis, monitoring and treatment. Current treatment of osteoarthritis does not influence progression. Much could be gained by more effective low-tech-low-cost treatment. However, many patients have rapidly progressive disease, multiple joint involvement, and severe disease. We need to clarify the genetics of osteoarthritis, identify those at risk for pr

Abstract is not available

Natural radiative lifetimes of eight levels in Tin I (4f(13)5d6p and 4f(12)5d682 configurations), two levels in Tin 11 (4f(12)5d6s configuration) and three levels in Tm III (4f(12)5d configuration) have been measured by using time-resolved laser spectroscopy. Free thulium atoms, as well as singly and doubly ionized ions, were obtained in a laser-induced thulium plasma and the investigated states w

Using bird atlas data from south-central Sweden and information on survey effort for the corresponding 5 x 5 km grid squares, we assessed how much time is required to get reliable presence/absence data for forest birds. We restricted the analyses to a suite of 28 species considered common enough and sufficiently generalised in their requirements to be present in all survey squares largely dominate

BACKGROUND: There are few data on how patients on maintenance treatment of reflux oesophagitis take their medication. This study was designed to investigate the dosing patterns of patients on on-demand treatment and to compare lansoprazole with omeprazole in this regard. METHODS: Patients with reflux oesophagitis, initially treated until absence of symptoms, took capsules of either lansoprazole (3

Effects on physical workload were quantified when introducing new information technology in air traffic control. Seven female and 7 male air traffic controllers were studied in an old control system, and during simulated-but similar-work in a new, mouse-based system. Postures, movements and muscular load were recorded (inclinometry for head, neck, back and upper arms; goniometry for wrists; elect

We report results from a theoretical study on the solvation of the divalent cations of Mg, Ca and Sr in water at infinite dilution. The ions are treated at the Hartree-Fock level with an explicit solvent model. Electrostatics, polarization and exchange repulsion contribute to the Hamiltonian. The dominating coordination number for the ions increases from 6 for Mg through 7 for Ca to 8 for Sr. A br

A subject may be in a state with nonconceptual content without having the concepts that describe the state. Nonconceptual content does not seem to be a clear-cut case of either implicit or explicit knowledge. It underlies a kind of practical knowledge that is not reducible to procedural knowledge, and is accessible to the subject and under voluntary control.

Given a steady and symmetric deep-water wave we prove that the surface profile and the vorticity distribution determine the wave motion completely throughout the fluid.

The development of treatment planning methods in radiation therapy requires dose calculation methods that are both accurate and general enough to provide a dose per unit monitor setting for a broad variety of fields and beam modifiers. The purpose of this work was to develop models for calculation of scatter and transmission for photon beam attenuators such as compensating filters, wedges, and blo

Abstract is not available

A chemical kinetics model for calculation of the formation of hydrogen cyanide (HCN) has been made. The combustion of a mixture of methylamine and ethylene has been modelled using the stationary laminar flamelet concept. The flamelet calculations are based on several thousand elementary reaction steps including the chemical kinetics of HCN in combustion. The flamelets for both cold (293 K) and hot

BACKGROUND: Peripheral blood progenitor cells (PBPCs) can be collected on various cell separators. Two leukapheresis programs (LP-MNC and LP-PBSC-Lym) were evaluated for computerized collection of PBPCs on a new cell separator. STUDY DESIGN AND METHODS: Leukapheresis assisted by the LP-MNC or LP-PBSC-Lym software was performed for the harvesting of PBPCs in 52 oncology patients after chemotherapy