Purpose:The aim of this study was to investigate the acute effects of p-synephrine ingestion on substrate oxidation during exercise in elite cyclists. Methods: Fifteen elite cyclists volunteered to participate in a double blind, crossover, randomized and placebocontrolled experimental trial. During two different trials, participants either ingested a placebo (cellulose) or 3 mg/kg of p-synephrine. After 60 min for substances absorption, participants performed an incremental maximal cycle ergometer test until volitional fatigue (25 W/min). Breath-by-breath gas exchange data was continuously recorded during the entire test to estimate energy expenditure, carbohydrate oxidation, and fat oxidation rates by stoichiometric equations. Heart rate was continuously measured by using a heart rate monitor. Results: The ingestion of p-synephrine had no significant effects on energy expenditure (F=0.71, P=0.40) or heart rate (F=0.66, P=0.43) during exercise. However, there was a main effect of p-synephrine to increase the rate of fat oxidation over the placebo (F=5.1, P=0.04) and the rate of fat oxidation was higher with p-synephrine in the following loads: 45±2%, 51±3%, 62±3%, 67±4%, 79±5% and 85±5% of the maximum wattage obtained in the test (all P<0.05). The ingestion of p-synephrine did not modify the maximal rate of fat oxidation during the ramp test (mean value; 95%CI = 0.91; 0.79-1.03 vs 1.01; 0.91-1.11 g/min, respectively, P=0.06) nor the exercise intensity at which maximal fat oxidation was achieved (i.e., Fatmax= 49; 48-53 vs 50; 47-51% Wmax, P=0.52). 3 Conclusion: Acute p-synephrine ingestion moved the fat oxidation-exercise intensity curve upwards during an incremental cycling test without affecting Fatmax.

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BACKGROUND: Growing environmental concern about the presence of pesticides in water demands their removal, particularly in industrial wastewater effluents. These streams are characterized by high content of organic colloidal matter. Physicochemical treatments based on the combination of coagulation-flocculation processes have been well studied. An integral treatment of a non-biodegradable agrochemical wastewater has been tackled by physicochemical treatment with polyferric chloride (PFC) followed by a homogeneous Fenton oxidation process. RESULTS:The potential coagulation and flocculation properties of PFC were evaluated for PFC solutions of different OH/Fe molar ratios. TOC removal of 81% was obtained in the coagulation-flocculation pre-treatment under the best operating conditions. The Fenton process with moderate dosage of hydrogen peroxide and 90 ∘ C also provided an extra 37% TOC reduction. The sludge from the physicochemical process was successfully activated with KOH at 750 ∘ C, obtaining a highly microporous material of 1240 m 2 g −1 of surface area. CONCLUSION: This work proposes a cost-effective approach to the treatment of a non-biodegradable agrochemical wastewater, achieving overall TOC reduction of 88%. The iron-containing sludge generated in the primary physicochemical treatment when treated by thermal treatment provides a promising adsorbent.

The biological removal of hydrogen sulfide at low concentration (<120 ppmv) was studied in a laboratory-scale biofilter packed with sugarcane bagasse and inoculated with a sulfur-oxidizing bacterial consortium isolated from activated sludge from a wastewater treatment plant (WWTP). Inlet loads from 1.31 to 20.2 g Sm(-3) h(-1) were supplied to the biofilter, and empty bed residence times (EBRTs) of 30, 20 and 10 s were tested. In all cases, the removal efficiency was greater than 99%. Two methods for the pH control were tested: increasing the phosphate buffer capacity of the mineral medium (method I), and a new method, which involves the addition of solid CaCO(3) to the bagasse at the upper inlet of the biofilter (method II). For method I, pH increased gradually along the bed (from the bottom to the top), from a constant value of 3.0 to 7.0. For method II, pH was constant (2.4 ± 0.8) along the bed, and then a steep increase of pH was observed at the top to 7.1. We suggest the use of CaCO(3) instead of phosphate buffer because the former is less expensive, it is a simple method and the results obtained with the two methods are similar.

The treatment of a non-biodegradable agrochemical wastewater has been studied by coupling of preliminary coagulation-flocculation step and further Fenton oxidation. High percentages of chemical oxygen demand (COD) removal (up to 58 %) were achieved in a first step using polyferric chloride as coagulant. This reduced significantly the amount of H2O2 required in the further Fenton oxidation. Using the stoichiometric amount relative to COD around 80 % of the remaining organic load was mineralized. The combined treatment allowed achieving the regional discharge limits of ecotoxicity at a cost substantially lower than the solution used so far where these wastewaters are managed as hazardous wastes.