The Leeds Evaluation of Efficacy of Detoxification Study (LEEDS) project: An open-label pragmatic randomised control trial comparing the efficacy of differing therapeutic agents for primary care detoxification from either street heroin or methadone [ISRCTN07752728]

BACKGROUND: Heroin is a synthetic opioid with an extensive illicit market leading to large numbers of people becoming addicted. Heroin users often present to community treatment services requesting detoxification and in the UK various agents are used to control symptoms of withdrawal. Dissatisfaction with methadone detoxification [8] has lead to the use of clonidine, lofexidine, buprenorphine and dihydrocodeine; however, there remains limited evaluative research. In Leeds, a city of 700,000 people in the North of England, dihydrocodeine is the detoxification agent of choice. Sublingual buprenorphine, however, is being introduced. The comparative value of these two drugs for helping people successfully and comfortably withdraw from heroin has never been compared in a randomised trial. Additionally, there is a paucity of research evaluating interventions among drug users in the primary care setting. This study seeks to address this by randomising drug users presenting in primary care to receive either dihydrocodeine or buprenorphine. METHODS/DESIGN: The Leeds Evaluation of Efficacy of Detoxification Study (LEEDS) project is a pragmatic randomised trial which will compare the open use of buprenorphine with dihydrocodeine for illicit opiate detoxification, in the UK primary care setting. The LEEDS project will involve consenting adults and will be run in specialist general practice surgeries throughout Leeds. The primary outcome will be the results of a urine opiate screening at the end of the detoxification regimen. Adverse effects and limited data to three and six months will be acquired

Prediction of the mass loss rate of polymer materials: Impact of residue formation

Two different numerical simulation tools, Fire Dynamic Simulator (FDS) and ThermaKin, are investigated with respect to their capability to predict the mass loss rate of polymer materials exposed to different fires. For validation, gasification apparatus and cone calorimeter tests are conducted. The main focus is on the influence of residue formation. Therefore, poly (butylene terephthalate) (PBT) and PBT reinforced with glass fibres (PBT-GF) are investigated and compared. PBT decomposes almost completely, while PBT-GF forms residue. The materials are characterised in order to provide suitable input parameters. Additionally the total incident heat flux to the sample is measured. With accurate input parameters, FDS and ThermaKin predicted the pyrolysis behaviour of PBT very well. Only some limitations are identified regarding the residue-forming PBT-GF. Both numerical simulation tools demonstrate a high value regarding the assessment of parameters' relative impacts and thus the evaluation of optimisation routes in polymer and composite development

Experimental study of radiative heat transfer in a translucent fuel sample exposed to different spectral sources

AbstractRadiative heat transfer to a solid is a key mechanism in fire dynamics, and in-depth absorption is especially of importance for translucent fuels. The sample-heater interaction for radiative heat transfer is experimentally investigated in this study with two different heaters (electric resistance and tungsten lamp) using clear PolyMethylMethAcrylate (PMMA) samples from two different formulations (Plexiglass and Lucite). First, the significant effects of the heater type and operating temperature on the radiative heat transfer are revealed with broadband measurements of transmittance on samples of different thicknesses. Then, the attenuation coefficient in Beer–Lambert’s law has been calculated from detailed spectral measurements over the full wavelength range encountered in real fires. The measurements present large spectral heterogeneity. These experimental results and calculation of in-depth absorption are used to explain the reason behind the apparent variation of the fuel absorbance with the sample thickness observed in past studies. The measurement of the spectral intensity emitted by the heaters verifies that the common assumption of blackbody behavior is correct for the electric resistance, whereas the tungsten lamp does not even behave as a greybody. This investigation proofs the necessity of a multi-band radiation model to calculate accurately the fire radiative heat transfer which affects directly the in-depth temperature profiles and hence the pyrolysis process for translucent fuel