The protection of children involved in prostitution act : case study and field analysis

The Protection of Children Involved in Prostitution (PCHIP) Act, which was passed in Alberta in 1999 and subject to immediate constitutional challenge, demonstrates the relationships between the fields of politics and law, and between youth criminal justice and child welfare legislation. The Act allowed authorities to apprehend and detain a youth engaged, or at risk of becoming engaged in prostitution for five to forty-seven days in a protective safe house. Though the PCHIP Act was passed as child welfare legislation, the punitive nature of the detainment led some to argue that the PCHIP Act was actually youth criminal justice legislation. This blurry boundary between child welfare and youth justice has negative consequences for particular groups of youth. In this case, Aboriginal female youth are disproportionately detained at protective safe houses. This research applies concepts from Pierre Bourdieu and other theorists to critically analyze the PCHIP Act as a case study. By drawing on various types of data, including the PCHIP Act, legislative debates, court transcripts, newspaper articles, government reports, and academic literature, two areas of inquiry are addressed. The first issue is the relationships and boundaries between the fields of politics and law, and between child welfare and youth criminal justice legislation. Secondly, this thesis attempts to explain why Aboriginal females are disproportionately confined by the PCHIP Act. This research concludes that the fields of politics and law constantly interact with each other, and the boundaries between child welfare and youth criminal justice are vulnerable to the outcomes of these conflict-ridden exchanges. These struggles, compounded by historical factors, have negative consequences for female Aboriginal youth in particular

Accretion of a satellite onto a spherical galaxy. II. Binary evolution and orbital decay

We study the dynamical evolution of a satellite orbiting outside of a companion spherical galaxy. The satellite is subject to a back-reaction force resulting from the density fluctuations excited in the primary stellar system. We evaluate this force using the linear response theory developed in Colpi and Pallavicini (1997). The force is computed in the reference frame comoving with the primary galaxy and is expanded in multipoles. To capture the relevant features of the physical process determining the evolution of the detached binary, we introduce in the Hamiltonian the harmonic potential as interaction potential among stars. The dynamics of the satellite is computed self-consistently. We determine the conditions for tidal capture of a satellite from an asymptotic free state. If the binary comes to existence as a bound pair, stability against orbital decay is lost near resonance. The time scale of binary coalescence is computed as a function of the eccentricity and mass ratio. In a comparison with Weinberg's perturbative technique we demonstrate that pinning the center of mass of the galaxy would induce a much larger torque on the satellite.Comment: 13 pages, Tex,+ 10 .ps figures Submitted to The Astrophysical Journa

Multi-excitonic complexes in single InGaN quantum dots

Cathodoluminescence spectra employing a shadow mask technique of InGaN layers grown by metal organic chemical vapor deposition on Si(111) substrates are reported. Sharp lines originating from InGaN quantum dots are observed. Temperature dependent measurements reveal thermally induced carrier redistribution between the quantum dots. Spectral diffusion is observed and was used as a tool to correlate up to three lines that originate from the same quantum dot. Variation of excitation density leads to identification of exciton and biexciton. Binding and anti-binding complexes are discovered.Comment: 3 pages, 4 figure

Polarized Emission Lines from Single InGaN/GaN Quantum Dots: Role of the Valence-band Structure of Wurtzite Group-III Nitrides

We present a study of the polarization properties of emission lines from single InGaN/GaN quantum dots (QDs). The QDs, formed by spinodal decomposition within ultra-thin InGaN quantum wells, are investigated using single-QD cathodoluminescence (CL). The emission lines exhibit a systematic linear polarization in the orthogonal crystal directions [1 1 -2 0] and [-1 1 0 0]--a symmetry that is non-native to hexagonal crystals. Eight-band k.p calculations reveal a mechanism that can explain the observed polarizations: The character of the hole(s) in an excitonic complex determines the polarization direction of the respective emission if the QD is slightly elongated. Transitions involving A-band holes are polarized parallel to the elongation; transitions involving B-type holes are polarized in the orthogonal direction. The energetic separation of both hole states is smaller than 10 meV. The mechanism leading to the linear polarizations is not restricted to InGaN QDs, but should occur in other wurtzite-nitride QDs and in materials with similar valence band structure.Comment: Conf. Proc. of the MSS-13 in Genova 2007, accepted at Physica

Ternary Fingerprints with Reference Odor for Fluctuation-Enhanced Sensing

An improved method for Fluctuation Enhanced Sensing (FES) is introduced. We enhanced the old binary fingerprinting method, where the fingerprint bit values were +/- 1, by introducing ternary fingerprints utilizing a reference odor. In the ternary method, the fingerprint bit values are -1, 0, and +1 where the 0 value stands for the situation where the slope of the spectrum is identical to that of the reference odor. The application of the reference odor spectrum makes the fingerprint relative to the reference. This feature increases the information entropy of the fingerprints. The method is briefly illustrated by sensing bacterial odor in cow manure isolates.Comment: submitted for publicatio

Dynamical friction and the evolution of satellites in virialized halos: the theory of linear response

The evolution of a small satellite inside a more massive truncated isothermal spherical halo is studied using both the Theory of Linear Response for dynamical friction and N-Body simulations. The analytical approach includes the effects of the gravitational wake, of the tidal deformation and the shift of the barycenter of the primary, so unifying the local versus global interpretation of dynamical friction. Sizes, masses, orbital energies and eccentricities are chosen as expected in hierarchical clustering models. We find that in general the drag force in self-gravitating backgrounds is weaker than in uniform media and that the orbital decay is not accompanied by a significant circularization. We also show that the dynamical friction time scale is weakly dependent on the initial circularity. We provide a fitting formula for the decay time that includes the effect of mass and angular momentum loss. Live satellites with dense cores can survive disruption up to an Hubble time within the primary, notwithstanding the initial choice of orbital parameters. Dwarf spheroidal satellites of the Milky Way, like Sagittarius A and Fornax, have already suffered mass stripping and, with their present masses, the sinking times exceed 10 Gyr even if they are on very eccentric orbits.Comment: 27 pages including 9 figures. Accepted for publication in the Astrophysical Journal. Part 2, issue November 10 1999, Volume 52

Static and Quasi-Dynamic Load Balancing in Parallel FDTD Codes for Signal Integrity, Power Integrity, and Packaging Applications

The Finite-Difference Time-Domain (FDTD) method is a robust technique for calculating electromagnetic fields, but practical problems, involving complex or large geometries, can require a long time to calculate on any one single-processor computer. One computer with many processors or many single-processor computers can reduce the computation time. However, some FDTD cell types, e.g., PML cells, require more computation time than others. Thus, the size and shape of the individual process allocations can significantly influence the computation time. This paper addresses these load balancing issues with static and quasi-dynamic approaches. The Message-Passing Interface (MPI) library is applied to a three-dimensional (3D) FDTD code. Timing results including speedup and efficiency, are presented for trials run on a cluster of sixteen processing, nodes and one server node. Two examples are shown in this paper, a power bus with 16 decoupling capacitors and a five layer power distribution network. In such models, the problem size and complexity make modeling with a serial code impractical and time consuming for engineering. Models with several million cells take days to run, but proper implementation, including load balancing, can reduce this execution time to hours on a sufficiently powerful cluster