Working girls: abuse or choice in street-level sex work? A study of homeless women in Nottingham

This paper aims to explore how abused homeless women understand their choice to sex work. In particular, there is a discussion of the motivations given by women as to why they sex worked, and it is suggested that abused homeless women can experience coercion from abusive partners in deciding to sex work. There is a challenge to the notion of 'victim' within the government's 'Prostitution Strategy' (Home Office, 2006) in specifying responses to the complex needs of sex working women. Recommendations are also made for practice in the context of the 'Strategy' when working with abused and coerced homeless women who choose to sex work. Twenty-six homeless women were interviewed - nine of whom had sex worked - and a structured, qualitative questionnaire was used in a case study design from which information was gathered about the relationship between a woman's experience of abuse and her decision to sex work

Mechanisms for the Oxonolysis of Ethene and Propene: Reliability of Quantum Chemical Predictions

Reactions of ozone with ethene and propene leading to primary ozonide (concerted and stepwise ozonolysis) or epoxide and singlet molecular oxygen (partial ozonolysis) are studied theoretically. The mechanism of concerted ozonolysis proceeds via a single transition structure which is a partial diradical. The transition structures and intermediates in the stepwise ozonolysis and partial ozonolysis mechanisms are singlet diradicals. Spin-restricted and unrestricted density functional methods are employed to calculate the structures of the closed-shell and diradical species. Although the partial diradicals exhibit moderate to pronounced instability in their RDFT and RHF solutions, RDFT is required to locate the transition structure for concerted ozonolysis. Spin projected fourth-order Møller–Plesset theory (PMP4) was used to correct the DFT energies. The calculated pre-exponential factors and activation energies for the concerted ozonolysis of ethene and propene are in good agreement with experimental values. However, the PMP4//DFT procedure incorrectly predicts the stepwise mechanism as the favored channel. UCCSD(T) predicts the concerted mechanism as the favored channel but significantly overestimates the activation energies. RCCSD(T) is found to be more accurate than UCCSD(T) for the calculation of the concerted mechanism but is not applicable to the diradical intermediates. The major difficulty in accurate prediction of the rate constant data for these reactions is the wide range of spin contamination for the reference UHF wave functions and UDFT solutions across the potential energy surface. The possibility of the partial ozonolysis mechanism being the source of epoxide observed in some experiments is discussed

Spot sampling of nutrient concentrations in the Puarenga catchment, Rotorua

The Centre for Biodiversity and Ecology Research was approached by Tūhourangi Tribal Authority for assistance with measuring water quality in streams in the Puarenga Stream catchment. Water sampling was subsequently undertaken on 18 July 2011 and samples were analysed to determine concentrations of total and dissolved fractions of nitrogen and phosphorus. Nitrogen and phosphorus are both essential plant nutrients which, when present in excess, can cause eutrophication and associated water quality decline of freshwaters. High concentrations of dissolved forms of nitrogen can also be toxic to aquatic organisms. Excessive nitrogen and phosphorus concentrations are typically the result of pollution due to human activities, although groundwater in the Central Volcanic Plateau region can have elevated concentrations of phosphorus arising from natural geological sources. This report summarises the methods used, presents the results and places measured concentrations in context by drawing comparisons with both guideline and regional mean values

On the origin of the Trojan asteroids: Effects of Jupiter's mass accretion and radial migration

We present analytic and numerical results which illustrate the effects of Jupiter's accretion of nebular gas and the planet's radial migration on its Trojan companions. Initially, we approximate the system by the planar circular restricted three-body problem and assume small Trojan libration amplitudes. Employing an adiabatic invariant calculation, we show that Jupiter's thirty-fold growth from a $10 M_\oplus$ core to its present mass causes the libration amplitudes of Trojan asteroids to shrink by a factor of about 2.5 to $\sim 40$ of their original size. The calculation also shows that Jupiter's radial migration has comparatively little effect on the Trojans; inward migration from 6.2 to 5.2 AU causes an increase in Trojan libration amplitudes of $\sim4$. In each case, the area enclosed by small tadpole orbits, if made dimensionless by using Jupiter's semimajor axis, is approximately conserved. Similar adiabatic invariant calculations for inclined and eccentric Trojans show that Jupiter's mass growth leaves the asteroid's eccentricities and inclinations essentially unchanged, while one AU of inward migration causes an increase in both of these quantities by $\sim 4$. Numerical integrations confirm and extend these analytic results. We demonstrate that our predictions remain valid for Trojans with small libration amplitudes even when the asteroids have low, butComment: Submitted to Icarus - 13 Fig

Facing Non-Stationary Conditions with a New Indicator of Entropy Increase: The Cassandra Algorithm

We address the problem of detecting non-stationary effects in time series (in particular fractal time series) by means of the Diffusion Entropy Method (DEM). This means that the experimental sequence under study, of size $N$, is explored with a window of size $L << N$. The DEM makes a wise use of the statistical information available and, consequently, in spite of the modest size of the window used, does succeed in revealing local statistical properties, and it shows how they change upon moving the windows along the experimental sequence. The method is expected to work also to predict catastrophic events before their occurrence.Comment: FRACTAL 2002 (Spain