Rhinologic changes in Wegener's granulomatosis

Twenty-eight patients with a clinical diagnosis of sinonasal Wegener's granulomatosis were referred for imaging during the period 1990-2001. Of these, 10 had clinical symptoms and signs confined to the nose and sinuses and 18 had classical systemic Wegener's. The computed tomography (CT) and magnetic resonance (MRI) scans of the series were reviewed by a panel of one otolaryngologist and two radiologists. From the total of 28 patients, 85.7 per cent showed non-specific mucosal thickening in the nasal cavity or paranasal sinuses, 75 per cent showed evidence of bone destruction, and 50 per cent new bone formation in the walls of the sinus cavities. In addition the orbit was affected in 30 per cent of patients.The diagnosis of systemic Wegener's granulomatosis is made clinically but the condition may present characteristic features on imaging by CT and MRI. In a patient without a history of previous sinonasal surgery, a combination of bone destruction and new bone formation on CT is virtually diagnostic of Wegener's especially when accompanied on MRI by a fat signal from the sclerotic sinus wall. These changes are important diagnostically in localized sinonasal Wegener's granulomatosis where the clinical diagnosis may be uncertain and the cANCA test can be negative

Optimizing the ensemble for equilibration in broad-histogram Monte Carlo simulations

We present an adaptive algorithm which optimizes the statistical-mechanical ensemble in a generalized broad-histogram Monte Carlo simulation to maximize the system's rate of round trips in total energy. The scaling of the mean round-trip time from the ground state to the maximum entropy state for this local-update method is found to be O([N log N]^2) for both the ferromagnetic and the fully frustrated 2D Ising model with N spins. Our new algorithm thereby substantially outperforms flat-histogram methods such as the Wang-Landau algorithm.Comment: 6 pages, 5 figure

Excessive Yawning and SSRI Therapy

As we become more experienced with the long-term use of selective serotonin reuptake inhibitors (SSRIs), more subtle side-effects may become evident. Clinicians may be aware of yawning as a side-effect of antidepressant therapy, however sparse literature exists on the topic. We present two cases in which excessive daytime yawning was associated with SSRI treatment

Characterisation of bulk water samples from copper pipes undergoing microbially influenced corrosion by diagnostic metabolomic profiling

This paper presents the application of metabolomic techniques to determine the presence of microbial influenced corrosion (MIC). In a previous study, the extracellular metabolites expressed from pipe biofilm was identified by analysing the passing water. This investigation extends this work by successfully applying a chemometric statistical analysis to the extracellular metabolomic profile of a number of water samples to identify critical metabolomic biomarkers. The chemometric analysis was able to differentiate samples due to a reduction of carboxylic acids in samples exposed to bacteria believed to cause MIC

Absolute differential positronium-formation cross sections

The first absolute experimental determinations of the differential cross-sections for the formation of ground-state positronium are presented for He, Ar, H2 and CO2 near 0○. Results are compared with available theories. The ratio of the differential and integrated cross-sections for the targets exposes the higher propensity for forward-emission of positronium formed from He and H2

System integration report

Several areas that arise from the system integration issue were examined. Intersystem analysis is discussed as it relates to software development, shared data bases and interfaces between TEMPUS and PLAID, shaded graphics rendering systems, object design (BUILD), the TEMPUS animation system, anthropometric lab integration, ongoing TEMPUS support and maintenance, and the impact of UNIX and local workstations on the OSDS environment

Development towards a portable instrument for the determination of pesticide residue in water

Pesticide contamination has been a widely publicised topic over the past 30 years and will continue to be a heated discussion point in the future. Given the level of scrutiny under which the water sector operates (namely for water quality, water availability and pricing), a robust technique is needed for the determination of pesticide residues in source waters that is both cost effective and reliable. This research project is aimed at developing such a technique to help water authorities meet this challenge. The method investigated utilised a flow injection system with tris(2,2’-bipyridyl)ruthenium(III) chemiluminescence detection (FICA) applied to the determination of atrazine, simazine, hexazinone, monocrotophos, and dicrotophos in natural waters. The FICA method presented utilises a chemically oxidized chemiluminescent reagent, which was optimised using a combination of multivariate and univariate optimisation procedures. The optimised experimental conditions were: sample and carrier flow rates of 4.6 mL min-1, sample at pH 9 buffered with 50 mM borax, and a reagent concentration of 1 mM tris(2,2’-bipyridyl)ruthenium(III) in 20 mM H2SO4 (pH 1) with a limit of detection of 1.3 ± 0.1 µg L-1 achieved for atrazine in MilliQ water. It was also shown that similar compounds, such as atrazine metabolites and other triazine pesticides, produced a chemiluminescent signal with tris(2,2-bipyridyl)ruthenium(III). When the method was applied to natural waters, the presence of dissolved organic matter (DOM) caused significant interference. This interference was investigated along with various cations and anions at levels commonly found in natural waters. It was observed that Fe3+ and Fe2+ (at concentrations above drinking water guidelines) caused interference. Fluorescence spectra were obtained for these samples to investigate the interaction between DOM, the selected pesticides and the interfering cations and anions. It was concluded that a complex formed between the analyte and DOM, and in the presence of interfering cations and anions the formation of the complex was enhanced. The interference from DOM was removed by solid phase extraction (SPE), and by incorporating an in-line SPE extraction column, the rapid detection of pesticide residues that had previously proven to be difficult due to interfering species was realised. A variety of extraction resins were evaluated for use in the in-line SPE housing, with Nexus© resin being the best of the ones tested. The detection limits achieved were 14, 48 and 32 ng L-1 for atrazine, hexazinone, and simazine, respectively. Lastly, a low-pressure monolithic column was merged with the in-line SPE FICA system in order to create a hybrid FIA system analogous to a low pressure HPLC system. The incorporation of a monolithic column enabled atrazine, simazine and hexazinone to be detected simultaneously with chromatographic differentiation, with method detection limits of 27, 39 and 60 ng L-1, respectively. The FICA system described in this thesis will be very useful as a quick, sensitive screening method for atrazine, simazine, hexazinone in natural waters. The methods developed during the course of this project should be considered by water utilities for inclusion in their ongoing pesticide monitoring programs