The Effects of Delta–9–Tetrahydrocannabinol, the primary psychoactive cannabinoid in marijuana, on human sperm function in vitro.

Objective: to investigate the effects of tetrahydrocannabinol; THC on human sperm function in vitro. Design: laboratory analysis of sperm motility with and without exposure to THC using computer assisted semen analysis (CASA) and acrosome reaction by fluoroscein isothiocyanate labelled peanut agglutinin (FITC-PNA) staining. Setting: An ART unit in a tertiary medical centre. Patients: semen was obtained from 78 men attending the Regional Fertility Centre, Belfast. Interventions: Sperm were divided into 90% (the best fertilizing potential used in assisted conception) and 45% (the poorer subpopulation) fractions by density centrifugation and incubated with, or without (controls), tetrahydrocannabinol (THC) at concentrations equivalent to therapeutic (0.032�?�¯?�?�­M) and recreational (4.8 and 0.32�?�¯?�?�­M) plasma levels, at 37�?�¯?�?�°C for 3 hours. Main outcome measures: Sperm motility, spontaneous and induced acrosome reactions Results: There was a dose-dependent decrease in percentage progressive motility (-21% at 4.8�??�?�µM, p0.05) in the 90% fraction. The 45% fraction showed a greater decrease in percentage progressive motility (-56% at 4.8�??�?�µM, p=0.011; -23% at 0.32�??�?�µM, p= 0.039; and -28% at 0.032�??�?�µM, p=0.004). A decrease in the straight line velocity; VSL (-10%) and the average path velocity; VAP (-10%) were also observed in the 90% fraction. A significant inhibition (-15% at 4.8�??�?�µM, p=0.04) in spontaneous acrosome reaction was observed in the 90% fraction. The 45% fraction showed a more marked inhibition [-35% (p

Dispersal mode and assessments of recovery on the shores of Gruinard, the 'anthrax island'

Formaldehyde run-off was an unintended impact of the anthrax decontamination procedure on the island of Gruinard. The death of intertidal organisms was observed where formaldehyde reached the shore during 1986. The extent to which shores on Gruinard have recovered was assessed with survey work in 2000. Recovery estimates were based on the hypothesis that the process of recolonization is partly dependent on species' dispersal capability. Underdevelopment of the assemblage of species lacking planktonic dispersal stages (direct developers) is therefore evidence that the process of recolonization is ongoing, rather than complete. A novel multivariate test showed that, when comparing quadrats from Gruinard and nearby mainland shores, assemblages of direct developing molluscs were significantly more distinct than assemblages of molluscs with planktonic dispersal stages. The average densities of species with direct development were generally lower on Gruinard than on mainland shores. While some species with direct development have similar densities on Gruinard and on the surrounding shores, the recovery of the overall assemblage was still incomplete after 14 years. In contrast, the harvested species, Littorina littorea, appeared to benefit from the absence of humans visiting Gruinard's shores. Populations of L. littorea on Gruinard contained significantly higher proportions of large individuals. Depending on the dispersal capabilities of different species, Gruinard is either still in recovery or acts as a reserve.

Conflict, Regulation and Marginalisation in the North of Ireland: The Experiences of Children and Young People

Based on primary research and consultations conducted over the last four years in the north of Ireland, this article considers the lives and experiences of children and young people in communities where the legacy of conflict and economic deprivation are most marked. It explores the reality of differential policing in communities where paramilitaries filled the policing deficit during the Conflict through informal 'justice' and punishment beatings. Finally, it considers the potential for change in a climate increasingly hostile towards children and young people, and the realisation of their rights.