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The acid-catalyzed pyrolysis of corncobs is investigated for the production of chemicals (in particular furfural) and bioproducts. Particles, preimpregnated with H2SO4 concentrations up to about 4% (dry sample mass basis) and predried at 343 K, are exposed in the form of a packed-bed at a heating temperature of 800 K. The gas release rate remains approximately constant, at a value about half with respect to the maximum detected for acid-free samples, for a large part of the process transients. Conversion times are roughly increased by 50% while reaction temperatures, on the average, become lower by about 20−40 K. Dehydrating and charring reactions become successively more favored suppressing the formation of condensable organic compounds. A decay is observed in the yields of both some carbohydrates (hydroxyacetaldehyde, hydroxypropanone, furfuryl alcohol, etc.) and phenolics (phenol, guiacol, 4-methyguaicol, 4-ethylguaicol, syringol) although less steep for the latter. However, catalyst concentrations below 0.5% lead to maxima in the yields of levoglucosan, 5-hydroxymethylfurfural, and 1,6-anhydro-β-d-glucofuranose. Moreover, the production is significantly enhanced of levoglucosenone (from trace amounts up to 4.5%) and furfural (from 0.65% up to 5%) at catalyst concentrations around 1−2% and 2−3%, with 1,4:3,6-dianhydro-α-d-glucopyranose (maximum yield 0.65%) acting as a reaction intermediate. The yield of acetic acid remains constant at 4% up to catalyst concentration around 3%. Higher catalyst concentrations are associated with a rapid decline in the yields of all these organic compounds with the total amount of char, carbon dioxide, and water reaching 70%.

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HighlightsBloodless surgery multidisciplinary approach.Management of Jehovah's witness patient.Patient-centered blood products use.

Objective: To investigate the effectiveness of a home-based preoperative rehabilitation program for improving preoperative lung function and surgical outcome of patients with chronic obstructive pulmonary disease (COPD) undergoing lobectomy for cancer. Methods: This was a prospective, observational, single-center study including 59 patients with mild COPD who underwent lobectomy for lung cancer. All patients attended a home-based preoperative rehabilitation program including a minimum of 3 sessions each week for 4 weeks. Each session included aerobic and anaerobic exercises. Participants recorded the frequency and the duration of exercise performed in a diary. The primary end point was to evaluate changes in lung function including predicted postoperative (PPO) forced expiratory volume in 1 second (FEV1), 6-minute walking distance test (6MWD), PPO diffusing capacity for carbon monoxide (DLCO) %, and blood gas analysis values before and after the rehabilitation program. Postoperative pulmonary complications were recorded and multivariable analysis was used to identify independent prognostic factors (secondary end point). Results: All patients completed the 4-week rehabilitation program. Thirteen of 59 (22%) patients (Group A) performed <3 sessions per week (mean sessions per week: 2.3±1.3); 46 of 59 (78%) patients (Group B) performed ⩾3 sessions per week (mean sessions per week: 3.5±1.6). The comparison of PPO FEV1% and 6MWD before and after rehabilitation showed a significant improvement only in Group B. No significant changes in PPO DLCO% or in blood gas analysis values were seen. Nine patients presented postoperative pulmonary complications, including atelectasis ( n = 6), pneumonia ( n = 1), respiratory failure ( n = 1), and pulmonary embolism ( n = 1). Group A presented higher number of postoperative pulmonary complications than Group B (6 vs 3; p = 0.0005). Multivariate analysis showed that the number of weekly rehabilitation sessions was the only independent predictive factor ( p = 0.001). Conclusions: Our simple and low-cost rehabilitation program could improve preoperative clinical function in patients with mild to moderate COPD undergoing lobectomy and reduce postoperative pulmonary complications. All patients should be motivated to complete at least 3 rehabilitation sessions per week in order to obtain significant clinical benefits. Our preliminary results should be confirmed by larger prospective studies.