Problems and Potential for Canadian Child Welfare

Canadian child welfare is not one single system, but more than 13 systems overseen by provincial and territorial governments and First Nations jurisdictions. However, there are many similarities among systems and general trends and directions common to them. One of these is a tendency for child welfare to become isolated from communities and related services because of its increasingly complex legislation and investigative mandates (Swift, 2001). Another is the challenge of serving peoples of diverse cultural and racial backgrounds, including First Nations peoples. Of course, each jurisdiction also responds to its particular social and political context in unique ways. In this paper we will present an overall picture of child welfare policies, services and trends across the country. We will also examine some unique and specific examples of ways child welfare organizations respond to local needs through the development of various kinds of partnerships. Highlighted in this paper will be some partnership developments with First Nations people and with diverse racial and cultural communities. Also highlighted are existing and potential partnerships with relevant service and advocacy organizations. We conclude with comments on implications of these partnerships for Canadian child welfare generally

Problems and Potential for Canadian Child Welfare

Canadian child welfare is not one single system, but more than 13 systems overseen by provincial and territorial governments and First Nations jurisdictions. However, there are many similarities among systems and general trends and directions common to them. One of these is a tendency for child welfare to become isolated from communities and related services because of its increasingly complex legislation and investigative mandates (Swift, 2001). Another is the challenge of serving peoples of diverse cultural and racial backgrounds, including First Nations peoples. Of course, each jurisdiction also responds to its particular social and political context in unique ways. In this paper we will present an overall picture of child welfare policies, services and trends across the country. We will also examine some unique and specific examples of ways child welfare organizations respond to local needs through the development of various kinds of partnerships. Highlighted in this paper will be some partnership developments with First Nations people and with diverse racial and cultural communities. Also highlighted are existing and potential partnerships with relevant service and advocacy organizations. We conclude with comments on implications of these partnerships for Canadian child welfare generally

Non-monotonous crossover between capillary condensation and interface localisation/delocalisation transition in binary polymer blends

Within self-consistent field theory we study the phase behaviour of a symmetric binary AB polymer blend confined into a thin film. The film surfaces interact with the monomers via short range potentials. One surface attracts the A component and the corresponding semi-infinite system exhibits a first order wetting transition. The surface interaction of the opposite surface is varied as to study the crossover from capillary condensation for symmetric surface fields to the interface localisation/delocalisation transition for antisymmetric surface fields. In the former case the phase diagram has a single critical point close to the bulk critical point. In the latter case the phase diagram exhibits two critical points which correspond to the prewetting critical points of the semi-infinite system. The crossover between these qualitatively different limiting behaviours occurs gradually, however, the critical temperature and the critical composition exhibit a non-monotonic dependence on the surface field.Comment: to appear in Europhys.Let

M-Dwarf Fast Rotators and the Detection of Relatively Young Multiple M-Star Systems

We have searched the Kepler light curves of ~3900 M-star targets for evidence of periodicities that indicate, by means of the effects of starspots, rapid stellar rotation. Several analysis techniques, including Fourier transforms, inspection of folded light curves, 'sonograms', and phase tracking of individual modulation cycles, were applied in order to distinguish the periodicities due to rapid rotation from those due to stellar pulsations, eclipsing binaries, or transiting planets. We find 178 Kepler M-star targets with rotation periods, P_rot, of < 2 days, and 110 with P_rot < 1 day. Some 30 of the 178 systems exhibit two or more independent short periods within the same Kepler photometric aperture, while several have three or more short periods. Adaptive optics imaging and modeling of the Kepler pixel response function for a subset of our sample support the conclusion that the targets with multiple periods are highly likely to be relatively young physical binary, triple, and even quadruple M star systems. We explore in detail the one object with four incommensurate periods all less than 1.2 days, and show that two of the periods arise from one of a close pair of stars, while the other two arise from the second star, which itself is probably a visual binary. If most of these M-star systems with multiple periods turn out to be bound M stars, this could prove a valuable way of discovering young hierarchical M-star systems; the same approach may also be applicable to G and K stars. The ~5% occurrence rate of rapid rotation among the ~3900 M star targets is consistent with spin evolution models that include an initial contraction phase followed by magnetic braking, wherein a typical M star can spend several hundred Myr before spinning down to periods longer than 2 days.Comment: 17 pages, 12 figures, 2 tables; accepted for publication in The Astrophysical Journa

Scaling of the Random-Field Ising Model at Zero Temperature

The exact determination of ground states of small systems is used in a scaling study of the random-field Ising model. While three variants of the model are found to be in the same universality class in 3 dimensions, the Gaussian and bimodal models behave distinctly in 4 dimensions with the latter apparently having a discontinuous jump in the magnetization. A finite-size scaling analysis is presented for this transition.Comment: 14 pages Latex, 4 figure

Shock and Release Temperatures in Molybdenum

Shock and release temperatures in Mo were calculated, taking account of heating from plastic flow predicted using the Steinberg-Guinan model. Plastic flow was calculated self-consistently with the shock jump conditions: this is necessary for a rigorous estimate of the locus of shock states accessible. The temperatures obtained were significantly higher than predicted assuming ideal hydrodynamic loading. The temperatures were compared with surface emission spectrometry measurements for Mo shocked to around 60GPa and then released into vacuum or into a LiF window. Shock loading was induced by the impact of a planar projectile, accelerated by high explosive or in a gas gun. Surface velocimetry showed an elastic wave at the start of release from the shocked state; the amplitude of the elastic wave matched the prediction to around 10%, indicating that the predicted flow stress in the shocked state was reasonable. The measured temperatures were consistent with the simulations, indicating that the fraction of plastic work converted to heat was in the range 70-100% for these loading conditions

Domain Coarsening in Systems Far from Equilibrium

The growth of domains of stripes evolving from random initial conditions is studied in numerical simulations of models of systems far from equilibrium such as Rayleigh-Benard convection. The scaling of the size of the domains deduced from the inverse width of the Fourier spectrum is studied for both potential and nonpotential models. The morphology of the domains and the defect structures are however quite different in the two cases, and evidence is presented for a second length scale in the nonpotential case.Comment: 11 pages, RevTeX; 3 uufiles encoded postscript figures appende

A temperature compensated fibre Bragg grating (FBG)-based sensor system for condition monitoring of electrified railway pantograph

This paper presents the results obtained from fibre Bragg grating (FBG) sensors integrated into a railway current-collecting pantograph for accurate measurement of contact force and contact location when it is infjected to various temperature conditions. The temperature change of the pantograph is simulated, at the industrial laboratory of Brecknell Willis in the UK, by changing the DC current applied to pantograph from 0 to 1500 A. This test is primarily designed to verify the effectiveness of the temperature compensation mechanism built in the FBG sensor design. For this verification, 3 thermocouples co-located with the FBG sensor packages are used to measure the temperature change seen from 25 °C to 55 °C. The tests were repeated several times and the sensor system has shown its temperatureindependence, confirming that the intrinsic cross-sensitivity of FBGs to temperature variation for strain measurement has been fully compensated through the use of this innovative sensor design and data processing

Work in Progress -- Instrumentation on a Truss Adapted for Pre-College Outreach

Engineering content is a valuable addition to pre-college instruction in science, technology, engineering, and mathematics (STEM) since it applies scientific concepts, illustrates scientific relevance and technology, and provides measurement opportunities. Also, complex systems and interactions can be shown. This work describes outreach resources using a seven-member instrumented truss apparatus. This aluminum bench-top model is scaled to support up to fifty pounds. Electrical resistance gauges are installed on several members for strain measurement. The resource set includes the truss apparatus, instrumentation, a PowerPoint presentation, and a background document. The pre-college objective is a set of demonstration resources for middle or high school classrooms. Effective outreach design is modeled by tailoring to accommodate curriculum standards, level-appropriate concept terms, and grade continuity. The resources were developed by students in an interdisciplinary college class on sensors and structures. The development activities involved testing the models and measurements and refining the construction. Selected resources were implemented and evaluated in a local middle school classroom. The interdisciplinary content includes structural, force analysis, sensing, and measurement components