Effectiveness of the combined effects of hypoxic gas mixture and electrical stimulation for the water-polo players` working ability correction

Two experiments were conducted to determine the combined effects of time on feed, high-voltage electrical stimulation (HVES) and postmortem aging on beef quality and palatability. Increasing time on feed resulted in an increase in carcass fat thickness, dressed carcass weight and marbling and a decrease in carcass lean content, carcass shrinkage and shear values in both experiments. Steaks from longer-fed animals were rated more highly for juiciness, tenderness and overall palatability by the consumers polled. HVES lowered muscle pH (3, 24 and 144 h), increased subjectively appraised marbling fat, gave brighter, redder muscle colour up to 6 d postmortem, and improved consumer ratings for flavour, juiciness, tenderness and overall palatability. HVES also resulted in a significant improvement in shear values (shear values were decreased by 27 and 35% in experiments 1 and 2, respectively). Aging for 6 d improved meat colour, decreased the amount of expressible juice and lowered the shear value of steaks by 11 and 9% respectively, in experiments 1 and 2. A consumer survey indicated that more than 20% of steaks were rated as unacceptable for tenderness when time on feed and postmortem aging were similar to Canadian beef-production practices. Incorporation of HVES as a means of quality control would reduce the proportion of unacceptable steaks to approximately 10%. Key words: Beef quality, time on feed, electrical stimulation, aging

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Delivery of an hypoxic gas mixture due to a defective rubber seal of a flowmeter control tube

European Journal of Anaesthesiology ◽

10.1097/00003643-200007000-00008 ◽

2000 ◽

Vol 17 (7) ◽

pp. 456-458 ◽

Cited By ~ 9

Author(s):

H. Hay

Keyword(s):

Gas Mixture ◽

Rubber Seal ◽

Control Tube ◽

Hypoxic Gas Mixture

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Hyperoxia prevents hypoxia-induced bronchial hyperreactivity via a cyclooxygenase-independent mechanism

Journal of Applied Physiology ◽

10.1152/jappl.1991.70.2.740 ◽

1991 ◽

Vol 70 (2) ◽

pp. 740-747 ◽

Cited By ~ 3

Author(s):

J. D'Brot ◽

T. Ahmed

Keyword(s):

Airway Responsiveness ◽

Prior Exposure ◽

Gas Mixture ◽

Protective Effects ◽

Bronchial Reactivity ◽

Independent Mechanism ◽

Before And After ◽

Sham Exposure ◽

Hypoxic Gas Mixture ◽

Dependent Mechanism

We tested the hypothesis that prior exposure to alveolar hyperoxia prevents the hypoxia-induced enhancement of bronchial reactivity, possibly via a cyclooxygenase-dependent mechanism. In 15 sheep, specific lung resistance (sRL) was measured before and after 30 min of exposure to either air or a hypoxic gas mixture (13% O2). The sheep then inhaled 50 breaths of aerosolized 5% histamine solution (n = 9) or 10 breaths of 2.5% carbachol solution (n = 9), and measurements of sRL were repeated. On subsequent days the above protocols were repeated after a 30-min exposure to hyperoxia (O2 greater than or equal to 95%), without or after pretreatment with indomethacin (2 mg/kg). After air-sham exposure, carbachol and histamine increased mean sRL to 370 +/- 40 (SE) and 309 +/- 65% of baseline, respectively. Exposure to the hypoxic gas mixture had no effect on baseline sRL but enhanced the airway responsiveness to carbachol and histamine; mean sRL increased to 740 +/- 104 and 544 +/- 76% of baseline, respectively (P less than 0.05). Prior 30-min exposure to hyperoxia prevented the hypoxia-induced enhancement of bronchial reactivity to carbachol (sRL = 416 +/- 66% of baseline) and histamine (sRL = 292 +/- 41% of baseline) without affecting the airway responsiveness to these agents after air. Pretreatment with indomethacin did not reverse the protective effects of hyperoxia or the hypoxia-induced enhancement of bronchial reactivity. We conclude that 1) prior exposure to alveolar hyperoxia prevents the hypoxia-induced enhancement of bronchial reactivity and 2) neither the protective effects of hyperoxia nor the hypoxia-induced enhancement of bronchial reactivity is mediated via a cyclooxygenase-dependent mechanism.

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Kinetics of Oxygen Uptake for Submaximal Exercise in Hyperoxia, Normoxia, and Hypoxia

Canadian Journal of Applied Physiology ◽

10.1139/h95-014 ◽

1995 ◽

Vol 20 (2) ◽

pp. 198-210 ◽

Cited By ~ 62

Author(s):

Richard L. Hughson ◽

John M. Kowalchuk

Keyword(s):

Ventilatory Threshold ◽

Binary Sequence ◽

Submaximal Exercise ◽

Work Rate ◽

Oxygen Deficit ◽

Gas Mixture ◽

Pseudorandom Binary Sequence ◽

Upper Limit ◽

Kinetics Of ◽

Hypoxic Gas Mixture

This study evaluated the dynamic response of [Formula: see text] in 6 healthy men at the onset and end of submaximal step changes in work rate during a pseudorandom binary sequence (PRBS) exercise test and during ramp incremental exercise to exhaustion while breathing three different gas mixtures. The fractional concentrations of inspired O2 were 0.14, 0.21, and 0.70 for the hypoxic, normoxic, and hyperoxic tests, respectively. Both maximal [Formula: see text] and work rate was significantly reduced in hypoxic tests compared to normoxic and hyperoxic tests. Maximal work rate was greater in hyperoxia than in normoxia. Work rate at ventilatory threshold was lower in hypoxia than in normoxia and hyperoxia but above the upper limit of exercise for the submaximal tests. Hypoxia significantly slowed the response of [Formula: see text] both at the onset and end of exercise compared to normoxia and hyperoxia. Hypoxia also modified the response to PRBS exercise, and again there was no difference between normoxia and hyperoxia. These data support the concept that [Formula: see text] kinetics can be slowed from the normoxic response by a hypoxic gas mixture. Key words: [Formula: see text]max, ventilatory threshold, oxygen deficit, pseudorandom binary sequence

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