RESUMEN
Deep coal reservoirs, as opposed to their shallower counterparts, exhibit characteristics of higher temperatures and pressures. These conditions affect the fracture structure and mechanical properties of coal, which in turn controls permeability. Substantial studies have been conducted to determine the effects of overburden pressure on permeability, but the correlation between the temperature and mechanical parameters/permeability of coal remains unclear. This study focused on low-rank bituminous coal from the southern edge of the Junggar Basin in Xinjiang. Using experiments conducted on seepage and mechanics at different depths (considering effective stress and temperature), the study investigated how temperature affects the mechanical parameters and permeability of coal column samples. A permeability prediction model was established incorporating temperature, mechanical parameters, and effective stress. The results show that from 20 to 80 °C, the elastic modulus of coal column samples decreases by 31.0%, and the Poisson ratio increases by 72.0%. Permeability decreases between 48.37 and 90.12% under different depths. The stress sensitivity coefficient under various temperature conditions decreased exponentially as the effective stress increased, and the temperature sensitivity coefficient under various effective stress conditions decreased with increasing temperature. The permeability was more sensitive to a temperature below 40 °C. In the permeability prediction model, the fracture compressibility coefficient is bifurcated into two coefficients, each controlled by temperature and effective stress. The permeability prediction error of the model was 12.7% under constant effective stress and 17.2% under varying effective stress and temperature conditions. The study could provide guidance for fracturing and coalbed methane production in deep coal reservoirs.
RESUMEN
OBJECTIVE: To evaluate the role of myositis-specific autoantibodies (MSAs) in interstitial lung disease (ILD), management of idiopathic inflammatory myopathies (IIM) associated ILD, and if there is a role for MSA specific management of ILD. METHODS: A systematic review was performed examining how MSAs relate to ILD manifestations in IIM patients and comparing treatment outcomes with varying immunosuppressive regimens. RESULTS: 112 papers were included in this analysis. Patients with anti-aminoacyl tRNA synthetase (anti-ARS) and anti-melanoma differentiation-associated gene 5 (anti-MDA5) antibodies had consistently higher rates of ILD than other MSA groups. Anti-ARS positive patients had higher rates of chronic ILD whereas anti-MDA5 positive patients had higher rates of rapidly progressive ILD (RP-ILD). The most common high-resolution computed tomography (HRCT) patterns for ILD in anti-ARS and anti-MDA5 positive patients were nonspecific interstitial pneumonia (NSIP) and unclassifiable respectively. Anti-transcription intermediary factor 1-gamma (anti-TIF1-γ), anti-Mi-2, anti-nuclear matrix protein 2 (anti-NXP-2), and anti-3-hydroxy-3-methylglutaryl coenzyme A reductase (anti-HMGCR) antibodies were associated with a decreased risk of ILD. Small sample sizes, a lack of head-to-head trials, and non-randomized designs prevented drawing meaningful conclusions with respect to immunosuppressive management. CONCLUSION: Clear relationships exist with regards to the ILD manifestations of certain MSAs. Standard therapy for IIM associated ILD (IIM-ILD) is glucocorticoids with the addition of others immunosuppressives in patients with or at risk of RP-ILD as well as in refractory cases. Immunosuppressives should be preferentially used in MSA populations in which they have been studied and shown to be efficacious.