G.M.N. Costa

Supercritical CO2 extraction of essential oils from Thymus vulgaris

Supercritical CO2 extraction of essential oil from Thymus vulgaris leaves was studied using experimental data recently obtained in the Florys S.p.A. laboratory. Mass transfer coefficients in the supercritical and solid phases from extraction curves at 40°C and 20 MPa were evaluated using a mathematical model based on the local adsorption equilibrium of essential oil on lipid in leaves. The adsorption equilibrium constant was fitted to these experimental data, and internal and external mass transfer resistances were calculated, allowing identification of the mechanism controlling the extraction process.

Rheumatic hand's clinical, functional and imagiological correlations following metacarpophalangeal joint silicone arthroplasty

Objective Evaluation of rheumatoid hand-associated metacarpophalangeal joint silicone arthroplasty most often relies on functional scores alone. This study aimed to understand the correlation between perceived and observed function, strength, and alignment. Methods Cross-sectional study including all 11 women (15 hands) submitted to second to fifth metacarpophalangeal joint arthroplasty due to rheumatoid arthritis involvement for a time period of seven years. Measurements relied on the Michigan Hand Outcomes Questionnaire, Lafayette Purdue Pegboard, pinch and grip strength, and analysis of a lateral “OK-sign” X-ray view. Correlation analysis used Spearmans coefficient, assuming statistical significance for p-values < 0.05. Results Objective function was strongly correlated with all other variables (p < 0.05), while perceived function failed to correlate with articular alignment in both measurements (p = 0.240 and p = 0.354). Strength and alignment were also strongly correlated (p < 0.05). Conclusions Most measurements strongly correlate with each other, with emphasis on objective dexterity measurement.