We studied 11 mild asthmatics to verify whether the mechanisms of hyperinflation in asthma could be inhibited or overcome by passively changing lung volumes. On day 1, we induced a fall in forced expiratory volume in one second (FEV1) of 30-60% by methacholine inhalation and measured the resulting increase in FRC (delta FRC). The delta FRC was 729 +/- 378 ml (mean +/- SD). On day 2, with the su...

This study evaluated the fracture load and failure mode of various veneer materials cemented with or without the addition of a fiber-reinforced composite (FRC) layer at the adhesive interface. Sixty intact incisors were randomly divided into three groups. Group 1 was fabricated with the heat-press technique (IPS Empress 2); Group 2 with the copy milling technique (ZirkonZahn); and Group 3 with ...

The purpose of this study was to investigate the effects of different cross-sectional shapes and presence of taper on stress distribution in clasp arms made of glass fiber-reinforced composite (FRC) material. Stress analysis of clasps was performed under a constant load (5 N) using a three-dimensional finite element method with due consideration to the anisotropy of unidirectional FRC material....

Functional residual capacity has been measured by helium dilution in 26 spontaneously breathing patients before and immediately after anaesthesia, which was induced with thiopentone and maintained with halothane. The mean reduction was 390 ml (16.1% or pre-induction value) and the change was highly significant (P less than 0.001). The decrease in FRC correlated with age (r equals 0.41: P less t...

In 19 asthmatic children, aged 2-6 years, the effect of six weeks' treatment with inhaled budesonide or placebo on functional residual capacity (FRC--helium dilution) and bronchodilator responsiveness was assessed in a double blind, randomised crossover trial. FRC was increased in most children at the start of treatment. Treatment with budesonide was associated with a reduction in FRC by compar...

In this paper we study empirically the Forward Rate Curve (frc) of 5 different currencies. We confirm and extend the findings of our previous investigation of the U.S. Forward Rate Curve. In particular, the average frc follows a square-root law, with a prefactor related to the spot volatility, suggesting a Value-at-Risk like pricing. We find a striking correlation between the instantaneous frc ...

BACKGROUND Positive expiratory pressure (PEP) and CPAP are used to enhance breathing parameters such as functional residual capacity (FRC) in patients. Studies comparing effects of PEP and CPAP on FRC are few and variable. One reason for this may be that sophisticated equipment, not suitable in the clinical setting, is required. Because total lung capacity (TLC) consists of inspiratory capacity...

BACKGROUND The Innocor device contains a highly sensitive photoacoustic gas analyser that has been used to perform multiple breath washout (MBW) measurements using very low concentrations of the tracer gas SF6. Use in smaller subjects has been restricted by the requirement for a gas analyser response time of <100 ms, in order to ensure accurate estimation of lung volumes at rapid ventilation ra...

BACKGROUND The respiratory mass spectrometer is the current gold-standard technique for performing multiple-breath inert gas washout (MBW), but is expensive and lacks portability. A number of alternative techniques have recently been described. OBJECTIVES We aimed to validate, using an in vitro lung model, an open-circuit MBW system that utilises a portable photoacoustic gas analyser, with su...

The lymph node vasculature is essential to immune function, but mechanisms regulating lymph node vascular maintenance and growth are not well understood. Vascular endothelial growth factor (VEGF) is an important mediator of lymph node endothelial cell proliferation in stimulated lymph nodes. It is expressed basally in lymph nodes and up-regulated upon lymph node stimulation, but the identity of...