Canadian Sex Work Policy for the 21st Century: Enhancing Rights and Safety, Lessons from Australia

This paper reviews the current problematic state of public policy addressed to the sex trade in Canada. It explores the recent parliamentary inquiry into the sex trade and suggests that the Canadian polity needs to set in train a clear program for reform in this area. A particular priority of these reforms should be to enhance the safety and rights of sex workers. At present the Canadian polity is mired in philosophic, moral and political divisions over the acceptability of sex work and this is limiting the search for practical ways of addressing urgent social problems. We argue that this search needs to be wide and continuing and that some practical ‘lessons’ can be learned from Australia where prostitution law reform has been in place for a considerable period of time

Clonal analysis of meningococci during a 26 year period prior to the introduction of meningococcal serogroup C vaccines

Meningococcal disease remains a public health burden in the UK and elsewhere. Invasive Neisseria meningitidis, isolated in Scotland between 1972 and 1998, were characterised retrospectively to examine the serogroup and clonal structure of the circulating population. 2607 isolates causing invasive disease were available for serogroup and MLST analysis whilst 2517 were available for multilocus sequence typing (MLST) analysis only. Serogroup distribution changed from year to year but serogroups B and C were dominant throughout. Serogroup B was dominant throughout the 1970s and early 1980s until serogroup C became dominant during the mid-1980s. The increase in serogroup C was not associated with one particular sequence type (ST) but was associated with a number of STs, including ST-8, ST-11, ST-206 and ST-334. This is in contrast to the increase in serogroup C disease seen in the 1990s that was due to expansion of the ST-11 clonal complex. While there was considerable diversity among the isolates (309 different STs among the 2607 isolates), a large proportion of isolates (59.9%) were associated with only 10 STs. These data highlight meningococcal diversity over time and the need for ongoing surveillance during the introduction of new meningococcal vaccines

Supernova cosmology: legacy and future

The discovery of dark energy by the first generation of high-redshift supernova surveys has generated enormous interest beyond cosmology and has dramatic implications for fundamental physics. Distance measurements using supernova explosions are the most direct probes of the expansion history of the Universe, making them extremely useful tools to study the cosmic fabric and the properties of gravity at the largest scales. The past decade has seen the confirmation of the original results. Type Ia supernovae are among the leading techniques to obtain high-precision measurements of the dark energy equation of state parameter, and in the near future, its time dependence. The success of these efforts depends on our ability to understand a large number of effects, mostly of astrophysical nature, influencing the observed flux at Earth. The frontier now lies in understanding if the observed phenomenon is due to vacuum energy, albeit its unnatural density, or some exotic new physics. Future surveys will address the systematic effects with improved calibration procedures and provide thousands of supernovae for detailed studies.Comment: Invited review, Annual Review of Nuclear and Particle Science (submitted version

The Phoenix Deep Survey: X-ray properties of faint radio sources

In this paper we use a 50ks XMM-Newton pointing overlapping with the Phoenix Deep Survey, a homogeneous radio survey reaching muJy sensitivities, to explore the X-ray properties and the evolution of star-forming galaxies. UV, optical and NIR photometry is available and is used to estimate photometric redshifts and spectral types for radio sources brighter than R=21.5mag (total of 82). Sources with R<21.5mag and spiral galaxy SEDs (34) are grouped into two redshift bins with a median of z=0.240 and 0.455 respectively. Stacking analysis for both the 0.5-2 and 2-8keV bands is performed on these subsamples. A high confidence level signal (>3.5sigma) is detected in the 0.5-2keV band corresponding to a mean flux of ~3e-16cgs for both subsamples. This flux translates to mean luminosities of ~5e40 and 1.5e41cgs for the z=0.240 and 0.455 subsamples respectively. Only a marginally significant signal (2.6sigma) is detected in the 2-8keV band for the z=0.455 subsample. We argue that the stacked signal above is dominated by star-formation. The mean L_X/L_B ratio and the mean L_X of the two subsamples are found to be higher than optically selected spirals and similar to starbursts. We also find that the mean L_X and L_1.4 of the faint radio sources studied here are consistent with the L_X-L_1.4 correlation of local star-forming galaxies. Moreover, the X-ray emissivity of sub-mJy sources to z~0.3 is found to be elevated compared to local HII galaxies. The observed increase is consistent with L_X evolution of the form (1+z)^3. Assuming that our sample is indeed dominated by starbursts this is direct evidence for evolution of such systems at X-ray wavelengths. Using an empirical L_X to SFR conversion we estimate a global SFR density at z~0.3 of \~0.029M_o/yr/Mpc in agreement with previous studies.Comment: 12 pages, 6 figures, accepted for publication in MNRA

The Phoenix Deep Survey: spectroscopic catalog

The Phoenix Deep Survey is a multi-wavelength survey based on deep 1.4 GHz radio imaging, reaching well into the sub-100 microJy level. One of the aims of this survey is to characterize the sub-mJy radio population, exploring its nature and evolution. In this paper we present the catalog and results of the spectroscopic observations aimed at characterizing the optically ``bright'' (R<~ 21.5 mag) counterparts of faint radio sources. Out of 371 sources with redshift determination, 21% have absorption lines only, 11% show AGN signatures, 32% are star-forming galaxies, 34% show narrow emission lines that do not allow detailed spectral classification (due to poor signal-to-noise ratio and/or lack of diagnostic emission lines) and the remaining 2% are identified with stars. For the star-forming galaxies with a Balmer decrement measurement we find a median extinction of A(Ha)=1.9 mag, higher than that of optically selected samples. This is a result of the radio selection, which is not biased against dusty systems. Using the available spectroscopic information, we estimate the radio luminosity function of star-forming galaxies in two independent redshift bins at z~0.1 and 0.3 respectively. We find direct evidence for strong luminosity evolution of these systems consistent with L(1.4 GHz) ~ (1+z)^(2.7).Comment: 39 pages, 12 figures. References added, and minor changes to reflect published versio

Remote sensing in Michigan for land resource management: Waterfowl habitat management at Pointe Mouillee

For many years the Pointe Mouillee State Game Area, located on the Lake Erie shoreline just south of Detroit, has been a prime waterfowl habitat. The usefulness of the site for this purpose has been impaired because of the gradual deterioration of the marshland and severe flooding and storms during the spring of 1973. Also, it has been proposed that a dredge spoils area be located in or near the marsh. To aid the future management of a diked refuge area of 148 hectares within the State Game Area, a detailed vegetation inventory was prepared by photointerpretation and a generalized vegetation inventory was obtained by processing multispectral scanner imagery. Also, an analysis was conducted to determine the magnitude of past losses of marshland and the possibilities of replacing this lost habitat. The analysis indicated that large additions to waterfowl habitat could be provided by changes in management of vegetation in existing sections of the State Game Area, through acquisition and conversion of adjacent land by the Michigan Department of Natural Resources, and by the proposed construction of a barrier dike offshore of Pointe Mouillee. Altogether, the various measures considered in this report could affect a total area of nearly 13 sq. km

Fully differential QCD corrections to single top quark final states

A new next-to-leading order Monte Carlo program for calculation of fully differential single top quark final states is described and first results presented. Both the s- and t-channel contributions are included.Comment: 3 pages, 3 figures, talk presented at DPF2000, August 9-12, 2000. To appear in International Journal of Modern Physics

Weak Localization Thickness Measurements of Si:P Delta-Layers

We report on our results for the characterization of Si:P delta-layers grown by low temperature molecular beam epitaxy. Our data shows that the effective thickness of a delta-layer can be obtained through a weak localization analysis of electrical transport measurements performed in perpendicular and parallel magnetic fields. An estimate of the diffusivity of phosphorous in silicon is obtained by applying this method to several samples annealed at 850 Celsius for intervals of zero to 15 minutes. With further refinements, this may prove to be the most precise method of measuring delta-layer widths developed to date, including that of Secondary Ion Mass Spectrometry analysis