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Experimental study on the influencing factors of using sewage sludge as a denitration agent for cement industry was carried out on a self-made laboratory-scale fluid-bed reactor. Results indicate that sludge combustion at 900 °C shows an ideal NOX (the sum of NO and NO2) removal activity under simulated working conditions of cement precalciner. The optimal removal efficiency of NOX can reach 70.36 ± 3.59% in the presence of cement raw meal (CRM) at a sludge particle size range of 0.18–0.25 mm and the sludge dosage of 0.75 g/min. Besides, the NOX removal efficiency increases to 76.94 ± 5.02% in the absence of CRM, indicating that cement raw meal inhibits the NOX removal. This phenomenon may be attributed to the fact that CRM has promotion effect on NH3 produced and obvious inhibitory effect on CO produced; while NH3 and CO play a leading role in NOX reduction, the combined effect leads to the decrease of NOX removal. Moreover, the relationship between the composition of CRM on the inhibition of NOX removal is MgO < CaCO3 < CRM < Al2O3 2O3. Meanwhile, the effect of additive variety on the sludge denitration activity indicates that urea significantly promotes the NOX removal, which is attributed to the decomposition of urea to form NH3. The stability experiment shows that sludge denitration efficiency remains stable above 70% in the presence of CRM and can reach over 80% when adding appropriate urea. This method can realize the removal of NOX in the cement kiln flue gas and the resource utilization of sludge. It is a promising method for sludge disposal. [ABSTRACT FROM AUTHOR]

Background and Purpose: There is a growing interest in use vibration foam rolling as a warm up and recovery tool. However, whether vibration foam rolling offers additional benefits to traditional foam rolling is unclear. The current study aims to compare the effects of acute foam rolling, with and without vibration, on skeletal muscle metabolism and microvascular reactivity., Methods: Fifteen physically active young males were tested on two different days, with gastrocnemius muscle microvascular function assessed using near-infrared spectroscopy coupled with the post-occlusive reactive hyperemia technique, before and after foam rolling, performed with or without vibration. The slope of tissue saturation index (TSI) decrease during occlusion between 120 s to 150 s (TSI occlusion slope) was assessed for muscle metabolic rate. Three commonly used microvascular function indexes, including the first10s TSI slope after occlusion (TSI10), time for TSI to reach half of peak magnitude (TSI1/2), and TSI peak reactive hyperemia, were also assessed., Results: None of the measured indexes showed significance for interaction or method (all p  > 0.05). However, there was a main effect for time for TSI occlusion slope, TSI1/2, and TSI peak reactive hyperemia ( p  = 0.005, 0.034 and 0.046, respectively). No main effect for time for TSI10 was detected ( p  = 0.963)., Conclusions: The application of foam rolling can decrease muscle metabolism, and may improve some aspects of muscle microvascular function. However, vibration foam rolling does not seem to offer any additional benefits compared to traditional foam rolling alone., Competing Interests: The authors declare there are no competing interests., (©2024 Huang et al.)

Purpose: The effects of coffee ingestion on skeletal muscle microvascular function are not well understood. This study aimed to investigate the acute effects of coffee intake with varying levels of caffeine on skeletal muscle microvascular reactivity at rest and oxygen extraction during maximal incremental exercise in physically active individuals., Methods: Twenty healthy young male participants were administered coffee with low caffeine (3 mg/kg body weight; LC), high caffeine (6 mg/kg body weight; HC), and placebo (decaf) in different sessions. Skeletal muscle reactivity indexes, including tissue saturation index 10s slope (TSI10) and TSI half time recovery (TSI ½) following 5-minute ischemia were measured at rest and were measured at baseline and post-coffee consumption using near-infrared spectroscopy (NIRS). Post-coffee intake, NIRS was also used to measure microvascular oxygen extraction during exercise via maximal incremental exercise. Peak oxygen consumption and peak power output (W peak ) were simultaneously evaluated., Results: Post-coffee consumption, TSI10 was significantly higher in the LC condition compared to placebo ( p  = 0.001) and significantly higher in the HC condition compared to placebo ( p  < 0.001). However, no difference was detected between LC and HC conditions ( p  = 0.527). HC condition also showed significant less TSI ½ compared to placebo ( p  = 0.005). However, no difference was detected for microvascular oxygen extraction during exercise, despite the greater W peak found for HC condition ( p  < 0.001) compared to placebo., Conclusion: Coffee ingestion with high caffeine level (6 mg/kg body weight) significantly enhanced skeletal muscle reactivity at rest. However, the improvement of exercise performance with coffee intake is not accompanied by alterations in muscle oxygen extraction.

Purpose: The analgesic effect of ropivacaine (Rop) for nerve block lasts only ~3-6 hours for single use. The aim of this study was to develop long-acting regional anesthetic Rop nanoparticles and investigate the effects of sciatic nerve block on postoperative pain in rats., Materials and Methods: Rop nanoparticles were developed using polyethylene glycol-co-polylactic acid (PELA). One hundred and twenty adult male Wistar rats were randomly divided into four groups (n=30, each): Con (control group; 0.9% saline, 200 µL), PELA (PELA group; 10 mg), Rop (Rop group; 0.5%, 200 µL), and Rop-PELA (Rop-PELA group; 10%, 10 mg). Another 12 rats were used for the detection of Rop concentration in plasma. The mechanical withdrawal threshold and thermal withdrawal latency were measured at 2 hours, 4 hours, 8 hours, 1 day, 2 days, 3 days, 5 days, and 7 days after incision. The expression of c-FOS was determined by immunohistochemistry at 2 hours, 8 hours, 48 hours, and 7 days. Nerve and organ toxicities were also evaluated at 7 days., Results: The duration of Rop absorption in the plasma of the Rop-PELA group was longer (>8 hours) than that of the Rop group (4 hours). Mechanical withdrawal threshold and thermal withdrawal latency in the Rop-PELA group were higher than that in other groups (4 hours-3 days). c-FOS expression in the Rop-PELA group was lower than that in the control group at 2 hours, 8 hours, and 48 hours and lower than that in the Rop group at 8 hours and 48 hours after paw incision. Slight foreign body reactions were observed surrounding the sciatic nerve at 7 days. No obvious pathophysiological change was found in the major organs after Rop-PELA administration at 7 days., Conclusion: Rop-PELA provides an effective analgesia for nerve block over 3 days after single administration, and the analgesic mechanism might be mediated by the regulation of spinal c-FOS expression. However, its potential long-term tissue toxicity needs to be further investigated.