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Notes: Radiation damage centers generated by x irradiation at 80 and 300 K in the storage phosphor RbI:Tl+ were investigated with optically detected magnetic resonance and optical measurements. It is shown that the intensity of the photostimulated luminescence depends on the concentration of Tl2+ centers. Bleaching into any of the seven identified Tl2+ absorption bands destroys the Tl2+ centers and leads to a Tl+ emission as well as to VK centers. Proportionally to photodestruction of Tl2+ centers, the photostimulated luminescence is decreased. The traps for information storage in RbI:Tl+ are F centers and Tl2+ centers. © 1996 American Institute of Physics.

Notes: The oxygen-free x-ray storage phosphor BaFBr, doped with Sr2+ and having Br− vacancies due to fluorine excess, is shown to have a high photostimulability shifted appreciably to lower photon energy compared to nondoped BaFBr because of the predominant generation of FA(Sr2+) centers on the Br− sublattice upon room-temperature x irradiation. The FA(Br−,Sr2+) centers are less stable than unperturbed F(Br−) centers. Therefore, the redshift of the photostimulability disappears upon thermal activation above room temperature. From the failure to observe an F center infrared emission, it is concluded that F and FA centers are spatially correlated to hole centers of yet unknown nature. © 1996 American Institute of Physics.

Notes: Background  In early 2001 in Australia there was a sudden and dramatic decrease in heroin availability that occurred throughout the country that was evidenced by marked increases in heroin price and decreases in its purity.Aim  This study examines the impact of this change in heroin supply on the following indicators of heroin use: fatal and non-fatal drug overdoses; treatment seeking for heroin dependence; injecting drug use; drug-specific offences; and general property offences. The study was conducted using data from three Australian States [New South Wales (NSW), Victoria (VIC) and South Australia (SA)].Methods  Data were obtained on fatal and non-fatal overdoses from hospital emergency departments (EDs), ambulance services and coronial systems; treatment entries for heroin dependence compiled by State health departments; numbers of needles and syringes distributed to drug users; and data on arrests for heroin-related incidents and property-related crime incidents compiled by State Police Services. Time-series analyses were conducted where possible to examine changes before and after the onset of the heroin shortage. These were supplemented with information drawn from studies involving interviews with injecting drug users.Results  After the reduction in heroin supply, fatal and non-fatal heroin overdoses decreased by between 40% and 85%. Despite some evidence of increased cocaine, methamphetamine and benzodiazepine use and reports of increases in harms related to their use, there were no increases recorded in the number of either non-fatal overdoses or deaths related to these drugs. There was a sustained decline in injecting drug use in NSW and VIC, as indicated by a substantial drop in the number of needles and syringes distributed (to 1999 levels in Victoria). There was a short-lived increase in property crime in NSW followed by a sustained reduction in such offences. SA and VIC did not show any marked change in the categories of property crime examined in the study.Conclusions  Substantial reductions in heroin availability have not occurred often, but in this Australian case a reduction had an aggregate positive impact in that it was associated with: reduced fatal and non-fatal heroin overdoses; reduced the apparent extent of injecting drug use in VIC and NSW; and may have contributed to reduced crime in NSW. All these changes provide substantial benefits to the community and some to heroin users. Documented shifts to other forms of drug use did not appear sufficient to produce increases in deaths, non-fatal overdoses or treatment seeking related to those drugs.

Notes: Background and aims  Heroin overdose is a serious consequence of heroin use and one of the leading causes of premature death and illness in Australia. Despite considerable research effort little is known about the effects of transient changes in heroin user behaviour and the links to overdose. This research is the first to use a suitable methodology to allow such ephemeral changes and their effects on non-fatal heroin overdose to be examined.Methods  A case-crossover design was used in which non-fatal heroin overdose survivors’ recall of risk behaviours in the 12 hours prior to overdose (hazard period) was compared to their recall of risk behaviours in the 12 hours prior to a selected non-overdose heroin injection (control period).Results  A total of 155 participants were able to provide valid details of hazard and control periods. A dose–response relationship was observed between the self-reported amount of heroin used and likelihood of overdose (e.g. 〉 AUD50, OR 12.97, 95% CI 2.54–66.31). The use of benzodiazepines (OR 28, 95% CI 3.81–205.79) or alcohol (OR 2.88, 95% CI 1.29–6.43), during the hazard period was related to overdose risk, but the effect of alcohol was attenuated by the effect of benzodiazepines. Shifting from private to public locations between control and hazard periods was also related to increased risk of overdose (OR 3.63, 95% CI 1.66–7.93).Conclusions  We demonstrate the value of a new methodology to explore heroin overdose, as well as discussing its limitations and ways to overcome them in future. In terms of our findings, overdose prevention messages need to highlight the impact of these transient changes in behaviour and to emphasize the risks of using higher doses of heroin as well as continuing to emphasize the risks of combining heroin with other central nervous system (CNS) depressants. Safer environments for heroin use, such as injecting rooms, may also reduce the chances of overdose.

Notes: We describe the clinicopathological findings in 12 cases of hepatic epithelioid haemangioendothelioma in order to identify diagnostic and prognostic features of this unusual vascular neoplasm. Three main tumour patterns were observed histologically: (1) a peripheral pattern with neoplastic cells scattered between fairly normal liver cell plates; (2) a cellular pattern showing a confusing admixture of pleomorphic tumour cells and atrophied hepatocytes set in a small amount of fibrous stroma; and (3) a scarred pattern with sparse tumour cells in a dense fibrous matrix. There were two types of vascular invasion: tuft-like intravascular proliferations of epithelioid cells and fibro-thrombotic venous occlusions. Awareness of these different aspects is important, as they are variably sampled by biopsy needles. The clinical course in this series was less favourable than that previously reported. Eight patients have died, in six instances of liver failure within 4–41 months of diagnosis. Extensive involvement of both lobes of the liver heralds imminent hepatic failure. The slow growth of metastases may justify liver transplantation in order to prolong life.