Precision Microwave Spectroscopy of the Positronium 2 ³S₁ → 2 ³P₂ Interval

We report the results of a new measurement of the positronium Precision Microwave Spectroscopy of the Positronium 2 ³S₁ → 2 ³P₂ (v₂) interval. Using a modified experimental arrangement we have significantly reduced the effects of microwave reflections, which in previous experiments resulted in shifts and asymmetric line shapes. With the improved apparatus we obtain an experimental value of v₂ = 8627.94 ± 0.95 MHz, which is within 1.3[sigma] of the theoretical value 8626.71 ± 0.08 MHz

Separation from Professional Employment Among Female Graduates of Canadian Schools of Social Work

There are several factors which affect the present position of social work as a profession. Historically, it is a relatively young profession. As such, there have been many changes as a state of stable professional identity is sought. Frmo what can be forecast, social work will continue to change, to borrow new knowledge from related professions, to develop new knowledge from within, to retain a dynamic and progressive view to self-improvement, and to work toward the general improvement of social conditions. While many things have changed, the problem of adequate manpower has not appreciably improved. The number of graduate social workers is growing slowly, but the unmet need for graduate social workers continues to grow much more rapidly. With such a need for graduate social workers, the problem of fully qualified persons leaving or separating from full-time professional employment after a few years becomes a most crucial issue

Vapour sorption, wavelength tracking and thermo-optic properties of dual slab waveguide interferometers

The dual slab waveguide interferometer is introduced as a device which has many applications in various research areas. Reported is its ability to provide details on the mechanism for the vapour sorption of thin polymer films, the development of the interferometer as a wavelength tracking device for the telecommunications industry and a method to characterise the thermo-optic properties of III-V semiconductor alloys. The vapour sorption mechanisms of thin films of polymers Polyisobutylene (PIB) and Polyvinylpyrrolidone (PVP) on exposure to several solvents are investigated. Coating interferometer chips with a thin layer of polymer and monitoring the interference fringe pattern for changes due to the exposure to a solvent vapour provides information on the mechanism for vapour sorption as one of swelling rather than void-filling. Interferometer sensitivities to vapour concentrations are linear and depend on refractive index differences between polymer and condensed vapour. An interferometer manufactured from III-V semiconductor compounds is developed to produce a device which can operate as a wavelength tracker. Sensitivities of over 6 mrad / pm and 7 mrad / pm for single and dual quaternary systems respectively indicate that a device of length around 5 mm would be capable of detecting picometer input wavelength changes including thermal background noise. The sensitivity to thermal changes provides a simple method for determining the thermo-optic coefficient of two Indium Gallium Arsenide Phosphide (InGaAsP) alloy compositions as (3.15±0.08)x 10(^-4)K(^-1) and (2.60±0.017)x10(^-4)k(6-1) forInGaAsP compounds with bandgap wavelengths around 1.3 μm and 1.15 μm respectively

Positronium formation at surfaces and studies towards the production of low energy antihydrogen

A magnetically guided slow positron beam has been used to measure positronium formation fractions via spectroscopy of annihilation radiation. Positrons with energies in the range 0-3 keV were implanted into tungsten, copper, magnesium oxide powder and silica aerogel targets at room temperature and at cryogenic temperatures (~30 K). This was done with and without nitrogen gas condensed on the surface of these materials. The resulting gamma rays were detected by a CsI detector and an associated PC-based spectroscopy system. In most cases studied the measured energy dependence of the positronium fractions was consistent with previous similar work, however, anomalous behaviour was found in some of the data when gas was condensed on metal surfaces. Using the same positron beam initial measurements of positronium energy distributions have been made. This was accomplished using a HPGe detector to measure the Doppler shift of the energy' of the positronium annihilation radiation. This novel technique has not yet been refined and estimates of its potential are reported. A Monte Carlo simulation of the reaction to form antihydrogen by positronium impact upon antiprotons has been undertaken. Total and differential cross sections have been utilised as input to the simulation which models the conditions foreseen in planned antihydrogen formation experiments using antiprotons and positrons held in Penning traps. Thus, predictions of antihydrogen production rates, angular distributions and the variation of the mean antihydrogen temperature as a function of the incident positronium energy have been made

Synthesis and Characterization of Mesoporous Silica Membranes Modified by Atomic and Molecular Layer Deposition

Inorganic membranes offer a means for chemical separations in a variety of applications including chemical processing, drug delivery systems, battery separators and fuel cells. There is currently a “pore size gap” in silica membranes between 1-2 nanometers. Synthesizing membranes with a fine control of the pore size and distribution within that gap is a significant challenge. This thesis reports findings on using atomic and molecular layer deposition as new synthesis approaches to controlling pore size and chemical functionality of silica membranes. Mesoporous silica membranes, prepared using surfactant-templates with pore diameters ~4nm, were modified using atomic layer deposition and molecular layer deposition. Atomic layer deposition was carried out using trimethyl aluminum and water as precursors and molecular layer deposition used trimethyl aluminum and oxalic and o-phthalic acid. These methods involved a separate pulse/purge sequence for each reactant that resulted in surface-limited film growth within the pores. It was determined that the growth rate of atomic layer deposition of alumina within mesoporous silica membranes was not linear, with a higher growth rate during the first 7 cycles and a lower rate afterwards. Alumina deposition was favored in larger pores within the pore size distribution of the support. The He/N2 selectivity of the membrane was improved by removing defects, although still in the Knudsen range. In preliminary work, the hydrothermal stability of the membrane increased as a result of the addition of alumina into the silica pore network. In the molecular layer deposition study, higher growth rates were observed when using oxalic acid as a precursor. Both oxalic and o-phthalic acid were able to increase the selectivity of the membrane above the He/N2 Knudsen value. Analysis of the permeance of several light gases suggested that pore size reduction occurred and that the modification was confined to a small layer within the support

Medication treatment perceptions, concerns and expectations among depressed individuals with Type I Bipolar Disorder

BACKGROUND: Subjective experience of illness affects outcomes among populations with bipolar disorder (BD). This cross-sectional study combined qualitative and quantitative approaches to evaluate perceived treatment effects, concerns and expectations among 90 individuals with BD. METHODS: Adults with type I BD, mean age 36.6 years, 51% women, completed a semi-structured interview that was audio taped, transcribed, coded and analyzed along emergent themes. Quantitative scales measured depressive symptoms (Hamilton Depression Scale/HAMD), psychopathology (Clinical Global Impression/CGI), and insight and treatment attitudes (Insight and Treatment Attitudes Questionnaire/ITAQ). RESULTS: Individuals had moderate depression and psychopathology with good insight into need for treatment. Drug treatment was perceived as beneficial, by “stabilizing” or “balancing” mood (42%, N=38), decreasing anxiety/depressive symptoms (19%, N=17) and improving sleep (10%, N=9). While 39%, (N=35) of individuals denied medication concerns, nearly 29%, (N=26) feared possible long-term effects, particularly diabetes or liver/kidney damage. Media stories and advertisements contributed to medication fears. Hopes and expectations for treatment ranged from those that were symptom or functional status-based, such as desiring mood stabilization and elimination of specific symptoms (23%, N=21), to more global hopes such as “being normal” (20%, N=18) or “cured” (18%, N=16). LIMITATIONS: Limitations include relatively small sample, lack of a comparator, inclusion of only depressed individuals and those willing to discuss their illness experience. CONCLUSIONS: While individuals with BD appreciate the effects of medications, concerns regarding adverse effects and discrepancy between actual and hoped-for outcomes can be substantial. Subjective experience with medications using qualitative and quantitative methods should be explored in order to optimize treatment collaboration and outcomes

S17RS SGB No. 8 (Amend SG Bylaws)

TO AMEND THE STUDENT GOVERNMENT BYLAW

Female reproductive strategy predicts preferences for sexual dimorphism in male faces

The aim of the current studies was to test an assumption that variation in female preferences for sexually dimorphic male facial characteristics reflects strategic optimisation of investment in offspring. A negative relationship was predicted between ideal number of children and preferences for masculine male face shapes, as the benefits of securing paternal investment should outweigh the benefits of securing good genes as the costs of raising offspring increase. In Study 1 desired number of children and preferences for masculine face shapes were compared in a sample of female students. In study 2, the prediction was tested in a sample with a wider age profile while controlling for relationship status. Preferences for explicit partner characteristics were also assessed. The prediction was supported: women who desired a higher number of children preferred more feminine male face shapes and ranked cues to investment of parental care over cues to immunocompetence in a partner more highly than those who desired fewer children. Results indicate that female mate preferences vary with reproductive strategy and support assumptions that preferences for feminine male faces reflect preferences for “good dads”