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Effect of free-stream turbulence on heat transfer and fluid flow in a transonic turbine stage

In the present work, a numerical study has been performed to simulate the effect of free-stream turbulence, length scale and variations in rotational speed of the rotor on heat transfer and fluid flow for a transonic high-pressure turbine stage with tip clearance. The stator and rotor rows interact via a mixing plane, which allows the stage to be computed in a steady manner. The focus is on turbin

Prenatal diagnosis of congenital heart defects-a population based study.

Aim: The aim of this study was to describe the efficiency of routine prenatal ultrasound screening for the detection of cardiac defects in a Swedish region and to study the effect of prenatal diagnosis on the survival and outcome of the child. Methods: We identified all fetuses and infants with a diagnosed major cardiac defect born in 1999-2003 in a region of Sweden using a register of the regiona

A new collimator simulation in SIMIND based on the delta-scattering technique

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

What can we do about osteoarthritis?

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

Lifetime measurements in TmI, TmII, and TmIII by time-resolved laser spectroscopy

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

How much time is required to survey land birds in forest-dominated atlas squares?

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

On-demand treatment in patients with oesophagitis and reflux symptoms: comparison of lansoprazole and omeprazole.

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

Changes in physical workload with implementation of mouse-based information technology in air traffic control

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

Combined quantum chemical statistical mechanical simulations of Mg2+, Ca2+ and Sr2+ in water

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

Nonconceptual content and the distinction between implicit and explicit knowledge

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.

Modeling transmission and scatter for photon beam attenuators

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