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The response of macrophages to monosodium urate crystals (MSUc) is incompletely understood partly due to the use of a toll-like receptor (TLR)-induced priming step in cell lines. Yet, MSUc induce inflammation in vivo without prior priming, raising the possibility of an initial cell-autonomous phase that is TLR-independent. Here, using genome wide transcriptomic analysis and biochemical assays we demonstrate that MSUc alone induce a metabolic-inflammatory transcriptional program in non-primed human and murine macrophages that is markedly distinct to that induced by LPS. Genes uniquely upregulated in response to MSUc belonged to lipid and amino acid metabolism, glycolysis, and SLC transporters. This upregulation led to a metabolic rewiring in sera from individuals and mice with acute gouty arthritis. Mechanistically, the initiating inflammatory-metabolic changes in acute gout flares are regulated through a persistent expression and increased binding of JUN to the promoter of target genes through JNK signaling -but not P38- in a process that is different than after LPS stimulation and unexpectedly independent of inflammasome activation. Finally, pharmacological JNK inhibition limited MSUc-induced inflammation in animal models of acute gouty inflammation. MSUc alone induce a unique strong macrophage activation and distinct phenotype that forces a reconsideration of initiating mechanisms in acute gout flares.

The preliminary design of an organic waste power plant utilizing both anaerobic digestion and solid oxide fuel cell (SOFC) technologies is presented along with a review of these technologies. Food waste and sewage sludge from a mid-sized Canadian municipality were modeled as feedstock for anaerobic digestion. The biogas quality and quantity produced from the digestion process were determined by modeling the municipal waste’s chemical composition and chemical oxygen demand (COD) content. Overall, between 480 kW and 1410 kW of electrical power can be produced from the SOFC system fueled by the biogas. The compatibility of these two technologies is evident and the major challenges and benefits associated with implementing this concept are discussed. This work demonstrates that an organic waste power plant is a sustainable solution to waste management and power production.

State-of-the-art sintering practices for metal injection molded (MIM) nickel superalloys (NiSAs) lead to fine-grain microstructures, reducing creep resistance compared to cast microstructures. MIM uses fine pre-alloyed powders which can increase prior particle boundary (PPB) carbide and oxide formation, restricting grain growth efforts. In the present work, the ability to activate grain growth in a MIM NiSA during supersolidus liquid phase sintering (SLPS) is evaluated using differential scanning calorimetry (DSC). A comparative DSC analysis technique was developed to quantify the SLPS liquid fraction with time and temperature and the grain growth behaviour of the MIM NiSA during SLPS was determined from optical microscopy. SEM-EDS of the sample microstructures revealed that the formation of refractory metal (RM)-Ta mixed MC carbides at the PPB restricts grain growth in the MIM NiSA. Time above the solidus temperature was found to dissolve the RM-Ta mixed MC carbides, enacting grain growth after a short incubation period. The results underscore the difficulty of accessing grain growth under the challenging conditions of MIM while demonstrating that SLPS can increase the grain size in the MIM NiSA.

The oxidation behavior of a fine Ni superalloy (NiSA) powder, Inconel 625, within an alumina support powder during heating has been determined using combined thermogravimetry (TG) and evolved gas analysis (EGA). A gas chromatographic-mass spectrometer (GCMS) was used for EGA. The GCMS was able to semi-quantitatively measure the rate at which air was removed from the furnace due to a He purge, where no pre-evacuation was used. It also was able to measure the effectiveness of a three cycle evacuation and He purge in reducing the oxygen content in the furnace and identify an important alumina off-gassing process that exposed the NiSA powder to H2O and CO2. The parallel use of the TG signal was able to quantitatively determine the relationship between NiSA oxidation and relative concentrations of the oxidizing gases created by the differing furnace pre-conditions and the alumina powder off-gassing process. It was concluded that the developed TG-GCMS method can be widely applied to quantitatively study oxygen pick-up in metal powders under industrially relevant processing conditions.

Wilderness therapy is a specialized approach to adolescent substance use and mental health treatment. While empirical evidence of positive outcomes grows to support this approach, qualitative understandings are lacking in the literature, thereby limiting theoretical explanations. Additionally, the voice of adolescent clients is hardly present, and was therefore the focus for this research. A sample of 148 adolescent wilderness therapy clients at one Canadian residential treatment program for addictive behaviour and mental health issues participated in the study. A realist approach utilizing thematic analysis of written open-ended responses produced six major themes; three depicting participant experiences (social dynamics, wilderness, catalyst for change) and three for perceived outcomes (skill development, self-concept, health). These findings are discussed in relationship to the development of a clinical model of wilderness therapy and the potential of wilderness interventions in adolescent residential treatment. Recommendations for practice and future research are discussed.