Long-short wavelength mode coupling tightens primordial black hole constraints

The effects of non-Gaussianity on the constraints on the primordial curvature perturbation power spectrum from primordial black holes (PBHs) are considered. We extend previous analyses to include the effects of coupling between the modes of the horizon scale at the time the PBH forms and superhorizon modes. We consider terms of up to third order in the Gaussian perturbation. For the weakest constraints on the abundance of PBHs in the early universe (corresponding to a fractional energy density of PBHs of 10−5 at the time of formation), in the case of Gaussian perturbations, constraints on the power spectrum are Pζ<0.05 but can be significantly tighter when even a small amount of non-Gaussianity is considered, to Pζ<0.01, and become approximately Pζ<0.003 in more special cases. Surprisingly, even when there is negative skew (which naively would suggest fewer areas of high density, leading to weaker constraints), we find that the constraints on the power spectrum become tighter than the purely Gaussian case—in strong contrast with previous results. We find that the constraints are highly sensitive to both the non-Gaussianity parameters as well as the amplitude of superhorizon perturbations

ANZAC- “coined out of material more precious than gold”: a look at how the Australian home front understood the Gallipoli campaign

Master of ArtsDepartment of HistoryAndrew OrrThis thesis will examine the home front of Australia during the Gallipoli campaign of 1915 in order to better understand how Australians conceived of the battle. It argues that individuals within the office of the prime minister self-consciously interpreted the battle in an attempt to establish a uniform national identity that was separate from British imperialism. It also argues that the campaign reinforced prewar gender roles for men and women. Historians have largely ignored the Australian home front during World War I and the immediate postwar period, focusing instead on how Gallipoli has been memorialized over time or on traditional military aspects of the campaign. Analyzing such themes as gender, identity, and race brings questions of citizenship and male and female gender roles into a perspective not yet adequately explored in historical literature. Applying these perspectives to the subject of Australia and Gallipoli, helps us to understand that the campaign was far more than merely a military engagement. It was a social experience that enabled the executive powers of the Australian government the ability to formulate a national identity and restructure society into the image it desired

Applicant Behavior on Internet Job Boards: The Effects of Content and Style

Although job boards are the largest single source of recruitment in the modern workplace, little research on what influences job seeker behavior has been conducted in this context. In order to address this gap in the literature, the present research draws on the theories of planned behavior and signaling theory to hypothesize a series of factors that may impact job seeker behavior. Despite theoretical support for many job posting characteristics, only formatting influenced job seeker behavior. Discussion of the implications and areas for future research are presented

Thermally and electrically induced antiferroelectric ↔ ferroelectric transition in perovskite ceramics for use in high energy density capacitors

Dielectric capacitors traditionally have very high power and short response time but low energy storage capability compared to batteries and electrochemical capacitors. For efficient and reliable energy storage of intermittent sources such as wind and solar, energy storage devices would ideally have both high power and energy densities. The studies of high energy density capacitor dielectrics presented in this thesis are part of the effort to move toward this paradigm. Ceramic antiferroelectric compositions such as Pb0.99Nb0.02[(Zr0.57Sn0.43)1-yTiy]0.98O3 (PNZST 43/100y/2) show promise as dielectrics in high energy density capacitors due to a sharp and highly tunable phase transition from antiferroelectric (AFE) to ferroelectric (FE). This transition results in a significant increase in polarization at a critical electric field, storing a large amount of electrical energy that can be released during unloading if the material undergoes the reverse transition at a relatively high electric field. These compositions also display thermally induced phase transitions, which must be understood in order to more fully understand how antiferroelectric properties develop. Several thermal characterization methods (dielectric constant and loss tangent, storage modulus and mechanical loss tangent, thermal expansion, and calorimetry) have been utilized to uncover the nature of complex phase transitions in lead-free pseudo-antiferroelectric composition (Bi1/2Na1/2)0.93Ba0.07TiO3 (BNT-7BT) and the lead-containing PNZST 43/8/2 composition. These experiments reveal the first order nature of the ferroelectric to antiferroelectric and the antiferroelectric to multi-cell cubic transitions, and the second order nature for the multi-cell cubic to single-cell cubic transition in PNZST43/8/2. In the BNT-7BT, the dielectric anomalies are not accompanied by any structural transitions in the unpoled state. However, after electrical poling to a ferroelectric phase with large domains, the thermal depolarization process corresponds to a first order structural transition. In general, the antiferroelectric to ferroelectric transition is accompanied with a volume expansion. Therefore, the critical field may be altered in specimens with varying electrode size, where the outer unpoled material exerts radial pressure on the expanding electroded material. The impact of electrode coverage on antiferroelectric PNZST43/100y/2 capacitors has been investigated at a series of temperatures in a series of compositions. Self-exerted mechanical confinement was found to shift the critical electric fields of the transitions to higher values and moderately increased the energy storage density. Phase field modeling reveals that, in addition to the self-confinement, material defects also contribute to these enhancements

Market-Oriented Subnational Debt Regimes: Empowering the Developing World to Construct Infrastructure

Globally, as national governments continue to decentralize fiscal and governmental responsibility, the sound facilitation of subnational debt markets will play a critical role in the construction of infrastructure. However, sparse scholarship exploring the optimal legal and financial frameworks for encouraging the construction of infrastructure at the subnational level has left a number of open questions. This Note primarily provides a basic overview of subnational debt trends and policies. It first reviews subnational debt regimes, comparing market-oriented regimes with regimes with varying levels of involvement by central governments. Though not always possible, the Note concludes that market-driven incentives generally produce the best subnational debt regimes. Though it has faced some struggles historically, as the largest and most liquid subnational debt market in the world, the United States\u27 municipal bond framework can provide a useful model. The Note then presents a market-oriented proposal for U.S. policy makers. By extending tax-exempt status to the public debt instruments of select subnational entities abroad, the United States could provide a promising investment opportunity for U.S. financial institutions and citizens, facilitate the construction of infrastructure in some of the most desperate areas of the world, and encourage sound international municipal finance practices through the extension of a largely self-regulated system. This market-enabling tax exemption could prove to be far more effective than any sort of direct spending. Finally, the Note argues that a fluid and competitive subnational debt market in developing countries is in the best interest of both investors and humanitarians alike

A rasch modelling approach to measuring school need for psychological services

The role and deployment of school psychologists in Western Australia has been reviewed a number of times since the establishment of services to schools. The current practice for the allocation of school psychologists to schools continues to rely on the student population of a school, its socioeconomic index and an appraisal of the school’s difficulty level. Psychological services are then allocated accordingly, with the decision-making mechanism based on an ad hoc conception of school need.The research reported in this study examined the issue of establishing the aspects or characteristics of schools which constitute a greater or lesser need for services and then attempts to measure this need in an objective, evidence-based manner. The various elements of school need for psychological services in Western Australia are posited to cluster around constructs extrapolated from the domains of service identified by Ysseldyke, Dawson, Lehr, Reschly, Reynolds, and Telzrow (1997), the delivery systems described by Oakland, Faulkner, and Annan (2005) and services delivered in Western Australia (Area Manager Student Services personal communication, 2007; Swan Education District Student Services Plan, 2009-2011; West Coast Education District Student Services Plan 2009-10). The constructs are characteristics of students, schools and teachers. These constituted the hypothesised theoretical framework for the study upon which the empirical investigation was based.The aims of the study are, first to make explicit the characteristics of schools, teachers and students that constitute concern and hence indicate the need for school psychological services. Second, to identify the characteristics of schools, teachers and students which differentiate the level of need for psychological services between schools and third, to demonstrate the validity of the instrument development process. The research questions were: 1. Can a rating scale instrument be developed to measure school personnel perceptions of their school’s need for psychological services? Specifically, in terms of measurement theory (Wright & Masters, 1982): (a) Was there uni-dimensionality? (b) Was there qualification? (c) Was there quantification? and (d) Was there linearity? 2. Is data from a measure of need for school psychological services associated with school demographic variables (e.g. socio-economic index)? 3. What facets of validity evidence described in the Wolfe and Smith (2007a and 2007b) framework are identifiable in the construction of a measure of school need for psychological services? Specifically: (a) Evidence of the content aspect; (b) Evidence of the substantive aspect; (c) Evidence of the structural aspect; (d) Evidence of the generalisability aspect; (e) Evidence of the interpretability aspect; (f) Evidence of the external aspect; and (g) Evidence of the consequential aspect?The methodology chosen for this research is quantitative and applies the principles of Modern Measurement Theory, using the Rasch Rating Scale model for measurement. The research was conducted in three developmental phases, with each phase building upon the preceding phase. First, theoretical framework refinement and item writing; second, developing and trialling a 120-item scale, leading to the third phase, the construction of a parsimonious 35-item scale which was used to measure the psychological service needs of a sample of schools. Careful documentation of the developmental process forms an important and necessary step in formulating a validity argument as evidence to support applications of the new measure. Furthermore, this has crucial implications for the credibility of any inferences that may be drawn from applying the instrument as an intended measure. In addition, publicly available school-level data were collected, such as socio-economic index, suspension and exclusion data, truancy, and students with individual behaviour management plans.The study identified examples of six aspects of validity evidence in the empirical investigation of school need for psychological services. This confirmed the usefulness of the multi-level theory of validity evidence postulated by Wolfe and Smith (2007a and 2007b). In addition, the analyses and graphical displays generated by the RUMM2020 computer program (Andrich, Sheridan, Lyne & Luo, 2005) proved invaluable in illustrating validity evidence. The measure of school need for psychological services was found to be significantly related to student suspensions data.The empirical findings of the study are discussed in the context of their application to informing decisions about the level of psychological services that should be provided to schools, congruent with measures of need for such services