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Melioidosis, caused by the environmental gramnegative bacterium Burkholderia pseudomallei, is endemic in northern Australia (1). The most common clinical manifestation of the infection is pneumonia, with or without bacteremia, but [...]

The burning of wood for bioenergy produces significant amounts of ash residue that requires disposal. We constructed a cost model to evaluate the unit costs of three ash disposal methods in the Canadian context: landfills owned and operated by the bioenergy facility, municipal landfills, and forest site application. The model accounts for costs related to the pretreatment, transportation, and disposal of ash at a landfill or forest site. Model parameter values were assigned appropriate distributions (based on published literature and industry surveys), and Monte Carlo simulations were employed to produce a range of model outputs for each disposal option. Results indicate that existing landfills (if available for ash disposal) are likely the most cost-effective option (median value of $77 per tonne), although applying ash to a forest site is only ~15%-20% more costly (median value of $92 per tonne). Indeed, the unit cost estimates across disposal options have considerable overlap. This suggests that close examination of firm-specific circumstances is highly warranted when choosing a disposal approach, even in the absence of accounting for potential environmental benefits associated with forest site disposal of ash. Key words: wood ash disposal, cost comparison, landfill disposal, forest application, Canada. La combustion du bois pour la bioenergie produit une quantite importante de cendre qui doit etre eliminee. Nous avons construit un modele de cout pour evaluer le cout unitaire de trois methodes d'elimination des cendres dans un contexte canadien, soit les sites d'enfouissement detenus et operes par l'industrie de la bioenergie, les sites d'enfouissement municipaux et l'epandage sur des sites forestiers. Le modele considere les couts lies au pretraitement, au transport et a l'elimination des cendres dans un site d'enfouissement ou un site forestier. Des distributions appropriees (selon la litterature et des enquetes aupres des industries) ont ete attribuees aux valeurs des parametres du modele et des simulations de Monte Carlo ont ete utilisees pour produire un eventail de resultats pour chaque option d'elimination. Les resultats indiquent que les sites d'enfouissement existants (a condition d'etre accessibles pour l'elimination des cendres) constituent vraisemblablement l'option la plus rentable (valeur mediane de 77 $ par tonne), bien que l'epandage des cendres sur un site forestier soit seulement environ 15 a 20 % plus couteux (valeur mediane de 92 $ par tonne). En fait, les couts unitaires estimes pour les diverses options d'elimination se chevauchent considerablement. Ceci porte a croire qu'un examen approfondi de la situation propre a chaque entreprise est plus que justifie pour choisir l'approche adequate d'elimination des residus, et ce meme sans tenir compte des benefices environnementaux potentiels associes a l'epandage des cendres sur un site forestier. [Traduit par la Redaction] Mots-cles: elimination de la cendre de bois, comparaison des couts, site d'enfouissement, epandage en foret, Canada., Introduction The use of forest biomass to generate energy is expected to increase as governments aspire to phase out traditional fossil fuels and the demand for renewably sourced energy grows. [...]

An interference resulting in the false-positive detection of the synthetic cathinone 4ʹ-methyl-α-pyrrolidinopropiophenone (4-MePPP) in urine was suspected following the recent addition of 4-MePPP spectral data to a liquid chromatography–quadrupole time-of-flightmass spectrometry drug library. Although positive detection criteria were achieved, it was noted that all urine samples suspected of containing 4-MePPP also concurrently contained high levels of tramadol and its associated metabolites. Using quadrupole time-of-flightmass spectrometry software elucidation tools, candidate compounds for the suspected interference were proposed. To provide further confidence in the identity of the interference, in silico fragmentation tools were used to match product ions generated in the analysis with product ions predicted from the theoretical fragmentation of candidate compounds. The ability of the suspected interference to subsequently produce the required product ions for spectral library identification of 4-MePPP was also tested. This information was used to provide a high preliminary confidence in the compound identity prior to purchase and subsequent confirmation with certified reference material. A co-eluting isobaric interference was identified and confirmed as an in-source fragment of the tramadol metabolite, N,N -bisdesmethyltramadol. Proposed resolutions for this interference are also described and subsequently validated by retrospective interrogation of previous cases of suspected interference. [ABSTRACT FROM AUTHOR]

Harvest residues are an attractive woody biomass feedstock for bioenergy production. A portion of the total harvest residues are generally left in the cutblock due to technical and profitability constraints. A better understanding of the factors influencing the variability of residue operational recovery rate is important to inform accurately policy development on sustainable forest biomass procurement practices. We compiled the results of field trials from boreal and temperate forests to quantify the range of variation of residue recovery rates and to identify the main factors explaining this variability. The average recovery rate was 52.2%, with minimum and maximum values of 4.0 and 89.1%, and a near-normal distribution around the average. The main factor contributing to this variation was country of operations, which encompasses aspects of bioenergy policy and markets, technological learning, and forestry context. A shift in bioenergy policy, a growth in (and a change in access to) bioenergy markets, and upward movements along the technological learning curve could increase residue recovery rates approaching the highest values observed in this study, such as those in Nordic countries (72% residue recovery), or even higher if economic and technological conditions keep improving. However, local stand conditions, especially in North America where natural variability is high among forest stands, may continue to constrain operational recovery of harvest residues. Our results suggest the need for the development of policies that define practices and thresholds based on the ecological suitability of ecosystems, with clear definitions and explicit standards for harvest residue inventory, quantification, and retention. WIREs Energy Environ 2015, 4:429-451. doi: 10.1002/wene.157 For further resources related to this article, please visit the . Conflict of interest: The authors have declared no conflicts of interest for this article. [ABSTRACT FROM AUTHOR]