Journal articles: 'Specific oxygen uptake rate'

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Tan, S. H., Jamaiatul Lailah M.J., and Aida Isma M.I. "Specific Oxygen Uptake Rate and Mass Transfer Coefficient in Activated Sludge System." Journal of Engineering & Technological Advances 4, no. 2 (2019): 24–32. http://dx.doi.org/10.35934/segi.v4i2.24.

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Activated sludge process is one of the effective methods in biological wastewater treatment and the impact of oxygen transfer through aeration process has the most important breakthroughs as it served as the largest consumer in the treatment. Aeration is an energy demanding process. Oxygen transfer into an activated sludge is a very challenging issue in the field of multiphase flows. Apart from the physical mass transfer phenomena between gas, liquid and solids phases, the transport mechanisms are also overlapped by time and temperature, varying microbial activity, impurity loads, adsorption and desorption processes. Oxygen uptake rate (OUR) for microbial population in the activated sludge system is important parameter to determine the amount of oxygen consumed during aerobic heterotropic biodegradation in the system. Evaluation of specific oxygen uptake rate (SOUR) and the volumetric mass transfer coefficient (KLA) of oxygen for three different wastewater treatment processes, namely conventional activated sludge (CAS), oxidation ditch (OD) and sequencing batch reactor (SBR) treating municipal wastewater in Kuala Lumpur have been carried out. In-situ and ex-situ measurement of pH, dissolved oxygen (DO), temperature, MLSS and MLVSS were carried out. In the activated sludge treatment, very low concentration of dissolved oxygen may cause the wastewater to turn septic resulting in death of bacteria or in active due to unstable anaerobic conditions. Conversely, an excessive dissolved oxygen may result to high energy and high 25 operating cost. Higher flowrate may also cause dissolved oxygen to rise, reducing the quality of sludge and slowing the denitrification process in the system. Results revealed that the OUR for SBR, OD and CAS were 9.582 mg O2 /L/hr, 10.074 mg O2 /L/hr and 13.764 mg O2 /L/hr, respectively. Low oxygen uptake rate indicates a low rate of microbial respiration. By computing the OUR, the mass transfer coefficient could be evaluated. It should be noted that among the treatment system in this study, the conventional activated sludge shows the highest mass transfer coefficient and specific oxygen uptake rate of 2.038 hr-1 and 15.605 mg O2 /g MLVSS/hr, respectively. Improving the oxygen transfer rate and reducing aeration in the system could achieve a cost-effective aeration system.

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Torres-López, Ana María, Juan Carlos Quintero-Díaz, and Lucía Atehortúa-Garcés. "Determination of the specific oxygen uptake rate in microorganisms including electrode time response." Revista Facultad de Ingeniería Universidad de Antioquia, no. 43 (February 25, 2014): 33–41. http://dx.doi.org/10.17533/udea.redin.18626.

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The oxygen transfer rate is an important parameter for the aerobic fermentative process. By establishing the real oxygen uptake rate of the target organism we can determine the energetic and process requirements for aeration and agitation. We report in this paper the mathematical and methodological procedure for the determination of the specific oxygen uptake rate (QO2 ), taking the oxygen electrode response into account. This methodology was applied to the QO2 determination for the Ganoderma lucidum medicinal mushroom while it was being cultured in a stirred reactor in the laboratory. The average value for QO2 was 0.345 mmol O2 (g biomass.h)-1± 0.0171 without taking the electrode time response into account and 0.383 mmol O2 (g biomass.h)-1± 0.025 taking the electrode time response into account. Higher response times of the oxygen electrode resulted in a greater differences between the two QO2 values obtained.

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Zubir, Arina Azmina Ahmad, Farrah Aini Dahalan, Nur Salsabila Kamarudin, et al. "Effect of Aeration Rate on Specific Oxygen Uptake Rate (SOUR) in Treating Chemical Oxygen Demand (COD) in Domestic Wastewater." IOP Conference Series: Earth and Environmental Science 1303, no. 1 (2024): 012026. http://dx.doi.org/10.1088/1755-1315/1303/1/012026.

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Abstract Specific oxygen uptake rate (SOUR) is significant parameter to determine the microbial activity and examined the effluent quality in biological wastewater treatment. Chemical oxygen demand (COD) is the major indicator in monitoring the effluent quality in relation on its removal mainly depends on the microbial activity in the activated sludge. So, this research is conducted to study the effect of aeration rate on SOUR and determined the best oxygen requirement in removing COD in domestic wastewater. The procedure was carried out by using domestic wastewater as the seed sludge in sequencing batch reactor. The reactor with working volume of 2L was operating 6 cycles in 24 hours with five phases (feeding, aeration, settle, draw and idle). The aeration time is fixed to 2.5 hours. The dissolved oxygen and COD readings were recorded with four types of aeration rate adjusted at 1L, 2L, 3L and 4L / min daily for 7 days. The result indicates that, 3L/min gives the highest SOUR which reflects that the high activity of microbial in this condition. Besides, the effluent also shows the highest COD removal efficiency on 3L/min of aeration rate. So, as a conclusion the best oxygen requirement for the microbial to carry out their activities on aeration rate of 3L/min.

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Pessôa Filho, Dalton Müller, Andrei Sancassani, Leandro Oliveira da Cruz Siqueira, et al. "Energetics contribution during no-gi Brazilian jiu jitsu sparring and its association with regional body composition." PLOS ONE 16, no. 11 (2021): e0259027. http://dx.doi.org/10.1371/journal.pone.0259027.

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We used measurements of metabolic perturbation obtained after sparring to estimate energetics contribution during no-gi Brazilian jiu-jitsu. Ten advanced grapplers performed two six-minute sparring bouts separated by 24 hours. Kinetics of recovery rate of oxygen uptake was modelled and post-combat-sparring blood-lactate concentration measured to estimate oxygen equivalents for phospholytic and glycolytic components of anaerobic energetics, respectively. Linear regression was used to estimate end-combat-sparring rate of oxygen uptake. Regional and whole-body composition were assessed using dual X-ray absorptiometry with associations between these measurements and energy turnover explored using Pearson’s correlation coefficient (significance, P < 0.05). Estimated oxygen equivalents for phospholytic and glycolytic contributions to anaerobic metabolism were 16.9 ± 8.4 (~28%) and 44.6 ± 13.5 (~72%) mL∙kg-1, respectively. Estimated end-exercise rate of oxygen uptake was 44.2 ± 7.0 mL∙kg-1∙min-1. Trunk lean mass was positively correlated with both total anaerobic and glycolytic-specific energetics (total, R = 0.645, p = 0.044; glycolytic, R = 0.692, p = 0.027) and negatively correlated with end-exercise rate of oxygen uptake (R = -0.650, p = 0.042). There were no correlations for any measurement of body composition and phospholytic-specific energetics. Six minutes of no-gi Brazilian jiu-jitsu sparring involves high relative contribution from the glycolytic component to total anaerobic energy provision and the link between this energetics profile and trunk lean mass is consistent with the predominance of ground-based combat that is unique for this combat sport. Training programs for Brazilian jiu-jitsu practitioners should be designed with consideration given to these specific energetics characteristics.

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He, Li, and Hui Pan. "Toxic Effects of Phenol on OUR in Activated Sludge." Advanced Materials Research 955-959 (June 2014): 2065–69. http://dx.doi.org/10.4028/www.scientific.net/amr.955-959.2065.

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Toxic effects of phenol on the activated sludge process were evaluated by determining the changes in DO in a laboratory-scale unit. A series of phenol concentration significantly affected the activated sludge. The effect of phenol was variable depending on its concentration. With the increase of phenol concentration, oxygen uptake rate (OUR) decreased. The inhibitory concentration that reduced the sludges specific oxygen uptake 50% from its maximum rate was determined (IC50).

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Ai, Sheng Shu, De Jun Bian, Qing Kai Ren, Yan Zuo, and Li Guo Wan. "Distribution Regularity of Organic Concentration in Multi-Flora Bioreactor." Advanced Materials Research 610-613 (December 2012): 1449–53. http://dx.doi.org/10.4028/www.scientific.net/amr.610-613.1449.

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The distribution regularity of organic concentration in treatment of wastewater by multi-flora bioreactor was investigated, and the correlation of the distribution regularity with sludge loading and specific oxygen uptake rate and microbial phase was analyzed. The experimental date show that, organic concentration in the reactor are uneven distribution trends, organic concentration are higher in the reactor bottom and bottom left, along the airflow direction, organic concentration are lower in the reactor left and upper part, and changes of organic concentration with sludge loading and specific oxygen uptake rate and microbial phase have some relevance.

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Bekraoui, Nabyl, Marie-Agnès Fargeas-Gluck, and Luc Léger. "Oxygen uptake and heart rate response of 6 standardized tennis drills." Applied Physiology, Nutrition, and Metabolism 37, no. 5 (2012): 982–89. http://dx.doi.org/10.1139/h2012-082.

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The purpose of this study was to compare the oxygen uptake of various on-court tennis drills. Eleven tennis players were monitored with a portable metabolic device to measure oxygen uptake of 6 different tennis drills at low and high speeds. The 6 drills were done with or without striking the ball, over half or full-width of the court, in attack or defense mode, using forehand or backhand strokes. Oxygen uptake values (mean ± SD) ranged from 33.8 ± 4.2 to 42.3 ± 5.1 mL·kg–1·min–1 when running at low speed on the full-width court in defense mode without striking the ball and when running at high speed on the full-width court in attack mode while striking the ball, respectively. Specific differences were observed. Attacking mode requires 6.5% more energy than defensive playing mode. Backhand strokes demand 7% more energy at low speed than forehand ones. Running and striking the ball costs 10% more energy than running without striking the ball. While striking the ball, shuttle running on half-width court costs 14% more energy than running on full-width courts. The specificity of the oxygen uptake responses obtained for these various tennis drills gives an improved representation of their energy cost and could be used to optimize training loads.

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Shamas, J. Y., and A. J. Englande. "Use of the Immediate Maximum Specific Oxygen Uptake Rate as an Activated Sludge Process Control Parameter." Water Science and Technology 25, no. 1 (1992): 123–32. http://dx.doi.org/10.2166/wst.1992.0019.

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The immediate maximum specific oxygen uptake rate (SOURim) was investigated as a potential process control parameter for the activated sludge system. Variability in effluent quality in terms of chemical oxygen demand correlated very well with the levels of SOURim at cell residence times of 3, 5, and 10 days. Transient response studied under batch growth conditions indicated a strong correlation between the SOURim, chemical oxygen demand, and the ribonucleic acid rates of change. The SOURim can therefore be used to qualitatively and quantitatively describe a given biomass thus making it a better suited parameter for use in process control strategies.

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Mu, Chenguang, Igor Soronovych, Andrii Diachenko, et al. "The Characteristics of Physical Fitness Related to Athletic Performance of Male and Female Sport Dancers." Sport Mont 19, S2 (2021): 125–30. http://dx.doi.org/10.26773/smj.210921.

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The aim of this research was to define specific characteristics of physical fitness of dancers and couples of dancers when analyzing them in relation to their dancing efficiency indices. Quantitative and qualitative char- acteristics of functional power, fast kinetics and economy indicated high requirements for the high function- ality of dancers-athletes. This can be seen from the indicators of the reaction power of the cardiorespiratory system and the energy supply of work. Differences of indicators: relative oxygen uptake (VO 2 max); pulmonary ventilation (V E ); carbon dioxide production (VCO 2 ), anaerobic threshold (AT) for both partners were statistically significant (р<0.05). At the same time, high requirements have been set for the fast kinetics and economy of the reaction. It is shown that the quantitative characteristics of the fast kinetics: half-time reaction of oxygen uptake (T 50 VO), pulmonary ventilation (T 50 VE); carbon dioxide production (T 50 VCO 2 ), heart rate ( T50 HR) and cost-effectiveness characteristics: oxygen heart rate at maximal oxygen uptake (VО 2 /HR at VO 2 max), oxygen heart rate at anaerobic threshold (VО 2 /HR at AT); ventilatory equivalent for carbon dioxide at anaerobic thresh- old (VE/VCO 2 at AT); ventilatory equivalent for carbon dioxide at maximal oxygen uptake (V E /VCO 2 at VO 2 max); ventilatory equivalent for oxygen at anaerobic threshold (VE/VO2 at AT); ventilatory equivalent for oxygen at maximal oxygen uptake (V E /VO 2 at VO 2 max); oxygen uptake percentage at anaerobic threshold from maximal oxygen uptake (%VO 2 АT from VO 2 max -1 ) between partners do not differ significantly. This made it possible to analyze the integral functional readiness of the pair and compare the characteristics of sportsmen-dancers of high and low qualifications.

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Oviedo, Ma D. Coello, D. Sales Márquez, R. Rodriguez-Barroso, and J. Ma Quiroga Alonso. "Inhibitory effects of non-ionic surfactants on the microbial activity of activated sludge system." Water Science and Technology 60, no. 4 (2009): 1033–39. http://dx.doi.org/10.2166/wst.2009.455.

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The purpose of the present work was to study the influence of a non-ionic surfactant, a nonylphenol with four ethoxylated units (NP4EO), on the activity of the microbial population present in a laboratory-scale activated sludge unit. Traditional control methods for this type of unit were used (measurement of suspended solids and chemical oxygen demand) as well as specific techniques for the measurement of bacterial activity (dehydrogenase activity and specific oxygen uptake rate) and the results were compared. It was shown that the Specific Oxygen Uptake Rate (SOUR) is the simplest and quickest way to carry out routine control of activated sludge activity, while measuring dehydrogenase activity provides more complete control. The results obtained indicated that there was no inhibition of microbial activity at a concentration of 5 ppm of NP4EO, which was not the case with a concentration of 10 ppm.

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Parkes, Roland, Lewis G. Halsey, Anthony J. Woakes, Roger L. Holder, and Patrick J. Butler. "Oxygen uptake during post dive recovery in a diving birdAythya fuligula: implications for optimal foraging models." Journal of Experimental Biology 205, no. 24 (2002): 3945–54. http://dx.doi.org/10.1242/jeb.205.24.3945.

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SUMMARYThe rate of oxygen uptake at the surface between dives was measured for four tufted ducks, Aythya fuligula, during bouts of foraging dives to a depth of 1.8 m. The ducks surfaced into a respirometer box after each dive so that the rate of oxygen uptake(V̇O2) could be measured. V̇O2decreased over time at the surface and there was a particularly rapid phase of oxygen uptake for approximately the first 3s. The specific shape of the oxygen uptake curve is dependent upon the duration of the preceding dive. The uptake curve after longer dives was significantly steeper during the first 3s at the surface than after shorter dives, although V̇O2 after the first 3s was not significantly different between these two dive duration bins. Thus, the mean total oxygen uptake (VO2) was higher after surface periods following longer dives. Due to the high V̇O2 during the initial part of the surface period, the curve associated with longer dives was statistically biphasic, with the point of inflection at 3.3s. The curve for shorter dives was not statistically biphasic. The birds may increase their respiratory frequency during the first 3s after longer dives, producing the increased V̇O2,which would enable the birds to resaturate their oxygen stores more rapidly in response to the increased oxygen depletion of the longer submergence time.

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Belur, Prasanna D., Floyd L. Inman, and Leonard D. Holmes. "Determination of specific oxygen uptake rate ofPhotorhabdus luminescensduring submerged culture in lab scale bioreactor." Biocontrol Science and Technology 23, no. 12 (2013): 1458–68. http://dx.doi.org/10.1080/09583157.2013.840361.

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Sampaio, F. C., P. Torre, F. M. LopesPassos, P. Perego, F. J. VieiraPassos, and A. Converti. "Xylose Metabolism in Debaryomyces hansenii UFV-170. Effect of the Specific Oxygen Uptake Rate." Biotechnology Progress 20, no. 6 (2004): 1641–50. http://dx.doi.org/10.1021/bp049691j.

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Rombough, P. J. "Partitioning of oxygen uptake between the gills and skin in fish larvae: a novel method for estimating cutaneous oxygen uptake." Journal of Experimental Biology 201, no. 11 (1998): 1763–69. http://dx.doi.org/10.1242/jeb.201.11.1763.

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The goal of this study was to develop an alternative to the traditional rubber dam method for measuring cutaneous oxygen uptake in bimodally respiring (skin + gills) fish larvae. The method tested involved using microelectrodes to measure the PO2 gradient in the diffusive boundary layer adjacent to seven positions on the skin surface (one on the head, two on the yolk sac, two on the trunk, one at the base of the dorsal fin-fold and one on the proximal portion of the caudal fin-fold) of rainbow trout (Oncorhynchus mykiss) larvae in still water. The PO2 gradient (deltaPO2/delta x, where x is the distance from the skin surface) was then used to calculate area-specific rate of O2 uptake (.MO2/A) according to the Fick equation, .MO2/A=Dbeta(deltaPO2/deltax), where A is the cross-sectional area of the boundary layer, D is the diffusion coefficient and beta is the capacitance coefficient for O2 in water. The accuracy of the method was assessed by comparing it with the rubber dam method. After correcting for differences in body mass, the two methods gave essentially identical results. According to the boundary layer method, the mean (+/-95 % CI) rate of O2 uptake across the skin of newly hatched rainbow trout at 10 degrees C is 3.13+/-0.18 microg O2 cm-2h-1 (N=265). The corresponding value obtained using the rubber dam method was 3. 36+/-0.35 microg O2 cm-2 h-1 (N=27). The advantages of the boundary layer method are that it can be used with smaller, more delicate larvae and that variables, such as flow rate, that can affect the efficiency of gas exchange can be regulated more precisely. The boundary layer method also permits examination of regional differences in exchange efficiency, although in still water such differences do not appear to be significant in trout larvae. The mean steepness of the PO2 gradient in the boundary layer and, hence, the mean rate of area-specific O2 uptake were essentially the same (P&gt;0.05) at all seven locations tested in this study. The boundary layer method can potentially be used to study the transcutaneous flux, not only of O2 but of virtually any diffusible substance that can be measured with microelectrodes and that is consumed (e.g. Na+, Ca2+) or excreted (e.g. CO2, NH3) by fish larvae or other small organisms.

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Pessôa Filho, Dalton M., Leandro O. C. Siqueira, Astor R. Simionato, Mário A. C. Espada, Daniel S. Pestana, and Fred J. DiMenna. "A Rapidly-Incremented Tethered-Swimming Test for Defining Domain-Specific Training Zones." Journal of Human Kinetics 57, no. 1 (2017): 117–28. http://dx.doi.org/10.1515/hukin-2017-0053.

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AbstractThe purpose of this study was to investigate whether a tethered-swimming incremental test comprising small increases in resistive force applied every 60 seconds could delineate the isocapnic region during rapidly-incremented exercise. Sixteen competitive swimmers (male, n = 11; female, n = 5) performed: (a) a test to determine highest force during 30 seconds of all-out tethered swimming (Favg) and the ΔF, which represented the difference between Favg and the force required to maintain body alignment (Fbase), and (b) an incremental test beginning with 60 seconds of tethered swimming against a load that exceeded Fbase by 30% of ΔF followed by increments of 5% of ΔF every 60 seconds. This incremental test was continued until the limit of tolerance with pulmonary gas exchange (rates of oxygen uptake and carbon dioxide production) and ventilatory (rate of minute ventilation) data collected breath by breath. These data were subsequently analyzed to determine whether two breakpoints defining the isocapnic region (i.e., gas exchange threshold and respiratory compensation point) were present. We also determined the peak rate of O2 uptake and exercise economy during the incremental test. The gas exchange threshold and respiratory compensation point were observed for each test such that the associated metabolic rates, which bound the heavy-intensity domain during constant-work-rate exercise, could be determined. Significant correlations (Spearman’s) were observed for exercise economy along with (a) peak rate of oxygen uptake (ρ = .562; p < 0.025), and (b) metabolic rate at gas exchange threshold (ρ = −.759; p < 0.005). A rapidly-incremented tethered-swimming test allows for determination of the metabolic rates that define zones for domain-specific constant-work-rate training.

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Survyla, Arnas, Donatas Levisauskas, Renaldas Urniezius, and Rimvydas Simutis. "An oxygen-uptake-rate-based estimator of the specific growth rate in Escherichia coli BL21 strains cultivation processes." Computational and Structural Biotechnology Journal 19 (2021): 5856–63. http://dx.doi.org/10.1016/j.csbj.2021.10.015.

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Urniezius, Renaldas, Deividas Masaitis, Donatas Levisauskas, Arnas Survyla, Povilas Babilius, and Dziuljeta Godoladze. "Adaptive control of the E. coli-specific growth rate in fed-batch cultivation based on oxygen uptake rate." Computational and Structural Biotechnology Journal 21 (2023): 5785–95. http://dx.doi.org/10.1016/j.csbj.2023.11.033.

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Casey, E., S. Rishell, B. Glennon, and G. Hamer. "Engineering aspects of a mixed methanotrophic culture in a membrane-aerated biofilm reactor." Water Science and Technology 49, no. 11-12 (2004): 255–62. http://dx.doi.org/10.2166/wst.2004.0855.

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Methanotrophic biodegradation using the membrane-aerated biofilm reactor (MABR) is a technology offering several advantages over both conventional biofilm reactors and suspended-cell processes. In this study the oxidation efficiency of a methanotrophic biofilm in a 1.5 litre MABR was investigated. Measurements of oxygen and methane uptake rates together with biofilm thickness were taken for developing biofilms. It was found that the specific rate of metabolic activity of the biofilm was unusually high as determined by the methane and oxygen uptake rates. Microbial activity stratification was evident and the location of stratified layers of oxygen consuming components of the consortium could be manipulated via the intra-membrane oxygen pressure.

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Rameshkannan, S., and B. Chittibabu. "Maximal oxygen uptake and cardiovascular adaptation to handball game specific endurance circuit training in handball players." Salud, Ciencia y Tecnología - Serie de Conferencias 3 (June 11, 2024): 882. http://dx.doi.org/10.56294/sctconf2024882.

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Now a day, the sports team coaches, trainers and other support staffs have a hectic job to deal with the preparation of their team players with consistent, precise and greater effort to meet the demands of the competition in shortest duration. Various training modalities were adopted depending upon the necessity that improves sports performance. Handball team coaches apparently felt that fitness and skill go hand in hand, where sports specific training caters to achieve this goal. Thus, the present study focussed on assessing the adaptations of maximal oxygen uptake and cardiovascular variables to handball game specific endurance circuit training. To accomplish the purpose twenty-four (24) trained university male handball players with a playing experience of more than eight years gave consent to participate. The selected twenty-four players were classified into two groups as Handball Game Specific Endurance Circuit Training Group (HGSECTG = 12) and Control Group (CG = 12). To test the effectiveness of handball game specific endurance circuit training (HGSECT) players performed specifically constructed handball circuit 3 days in a week for 12 weeks at 90-95% of maximal heart rate for two minutes duration and active recovery by walking. HGSECTG showed significant improvement on maximal oxygen uptake (t = 8.516, p < 0.05) and distance covered in Yo-Yo test also increased (t = 8.4, p < 0.05). Similarly, cardiovascular modifications are noted in maximum heart rate (HRPEAK, t = 2.372, p < 0.05) and resting heart rate (HRREST, t = 3.975, p < 0.05) and percentage of heart rate reserve (%HRRESERVE, t = 3.004, p < 0.05). We conclude that handball game specific endurance training programs could be sufficiently suitable to develop maximal oxygen uptake and positive adaptation of cardiovascular variables in twelve weeks of training among handball players. The intensity, duration, frequency and recovery of the intervention displayed improvement in VO2PEAK with reduced condition on cardiovascular stress.

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Watts, Phillip B., Jon Eric Sulentic, Kip M. Drobish, et al. "Physiological Responses to Specific Maximal Exercise Tests for Cross-Country Skiing." Canadian Journal of Applied Physiology 18, no. 4 (1993): 359–65. http://dx.doi.org/10.1139/h93-030.

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The present study attempted to quantify differences in peak physiological responses to pole-striding (PS), double poling on roller skis (DP), and diagonal striding on roller skis (DS) during maximal exercise. Six expert cross-country ski racers (3 M, 3 F) with a mean age of 20.2 ± 1.3 yrs served as subjects. Testing was conducted on a motorized ski treadmill with a tracked belt surface. Expired air was analyzed continuously via an automated open-circuit system and averaged each 20 s. Heart rate was monitored via telemetry and arterialized blood was collected within 1 min of test termination and analyzed immediately for lactate. Peak values for heart rate and blood lactate did not differ among techniques. Peak oxygen uptake was higher for PS and DS versus DP whereas no difference was found between PS and DS. The VO2 peak for DP was 77 and 81% of VO2 peak for PS and DS, respectively. It was concluded that despite similar peak heart rate and blood lactate values, DP elicits a lower VO2 peak than DS or PS and that PS responses appear to closely reflect those of DS. Key words: exercise testing, maximum oxygen uptake, roller skiing, specificity of exercise, x-c skiing

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Kim, James, Omokhowa Agbojo, Sunghoon Jung, and Matt Croughan. "Measurement of Oxygen Transfer Rate and Specific Oxygen Uptake Rate of h-iPSC Aggregates in Vertical Wheel Bioreactors to Predict Maximum Cell Density Before Oxygen Limitation." Bioengineering 12, no. 4 (2025): 332. https://doi.org/10.3390/bioengineering12040332.

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The prediction of the cell yield in large-scale bioreactor culture is an important factor for various cell therapy bioprocess operations to ensure consistency in cell quality and efficient use of resources. However, the shear sensitivity of cells used in cell therapy manufacturing can make such predictions difficult, particularly in large-scale suspension cultures that have significant stresses without representative scale down models. The PBS Vertical-Wheel (VW) bioreactors have been demonstrated to provide a homogeneous hydrodynamic environment with low shear for cell culture at various scales (0.1–80 L) and is thereby employed for various shear-sensitive cells. In this study, the oxygen transfer rate for surface aeration for three large-scale VW bioreactors was measured along with the specific oxygen uptake rate (sOUR) of iPSCs cultured in the bioreactors. The oxygen mass transfer coefficient was measured in PBS-3/15/80 L bioreactors at different agitation rates, headspace gas flowrates, and working volumes using the static gassing-out method. The sOUR of iPSCs was measured using the dynamic method in the PBS-0.1 L Mini with a custom DO probe configuration. The results from both experiments were combined to calculate the theoretical maximum cell density before oxygen limitation across VW bioreactors at 2 L/3 L/10 L/15 L/50 L/80 L working volumes at a different agitation speed and aeration rate.

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Rowe, G. E., A. Margaritis, and N. Wei. "Specific Oxygen Uptake Rate Variations during Batch Fermentation of Bacillus thuringiensis Subspecies kurstaki HD-1." Biotechnology Progress 19, no. 5 (2003): 1439–43. http://dx.doi.org/10.1021/bp030018o.

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Dahlmann, Katharina, Christoph Busse, Florian Aupert, et al. "Online monitoring of the cell-specific oxygen uptake rate with an in situ combi-sensor." Analytical and Bioanalytical Chemistry 412, no. 9 (2019): 2111–21. http://dx.doi.org/10.1007/s00216-019-02260-9.

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Davidson, Pavel, Huy Trinh, Sakari Vekki, and Philipp Müller. "Surrogate Modelling for Oxygen Uptake PredictionUsing LSTM Neural Network." Sensors 23, no. 4 (2023): 2249. http://dx.doi.org/10.3390/s23042249.

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Oxygen uptake (V̇O2) is an important metric in any exercise test including walking and running. It can be measured using portable spirometers or metabolic analyzers. Those devices are, however, not suitable for constant use by consumers due to their costs, difficulty of operation and their intervening in the physical integrity of their users. Therefore, it is important to develop approaches for the indirect estimation of V̇O2-based measurements of motion parameters, heart rate data and application-specific measurements from consumer-grade sensors. Typically, these approaches are based on linear regression models or neural networks. This study investigates how motion data contribute to V̇O2 estimation accuracy during unconstrained running and walking. The results suggest that a long short term memory (LSTM) neural network can predict oxygen consumption with an accuracy of 2.49 mL/min/kg (95% limits of agreement) based only on speed, speed change, cadence and vertical oscillation measurements from an inertial navigation system combined with a Global Positioning System (INS/GPS) device developed by our group, worn on the torso. Combining motion data and heart rate data can significantly improve the V̇O2 estimation resulting in approximately 1.7–1.9 times smaller prediction errors than using only motion or heart rate data.

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Chinet, A. E., and J. Mejsnar. "Is resting muscle oxygen uptake controlled by oxygen availability to cells?" Journal of Applied Physiology 66, no. 1 (1989): 253–60. http://dx.doi.org/10.1152/jappl.1989.66.1.253.

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To estimate oxidative capacity of noncontracting rat skeletal muscle, the isolated gracilis muscle was perfused at various high flow rates with high-PO2 (88 kPa) saline-albumin solution and simultaneously perifused at either low (6.3 kPa) or high PO2 in a calorimeter at 28 degrees C. Under low-PO2 perifusion, specific O2 consumption and heat production rates (MO2 and E, respectively) were flow-rate dependent. E values were all larger than those obtained on blood-perfused preparations at 28 degrees C. MO2 reached 0.47 mumol.min-1.g muscle-1 and E reached 4 mW/g. Normalized to 36 degrees C by means of activation energies determined from 30 and 36 degrees C measurements on nonperfused gracilis strips, these maxima correspond to three times the largest MO2 measured by other authors in blood-autoperfused gracilis. Increasing perifusion PO2 from 6.3 to 88 kPa sharply decreased MO2. These results confirm that MO2 of blood-perfused skeletal muscles in vitro (and a fortiori in vivo) is kept much below its maximum for a noncontracting organ; they also suggest that this maximum MO2 is not necessarily an effect of unphysiologically high PO2 in the tissue cells.

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Wilkinson, Michael, Damon Leedale-Brown, and Edward M. Winter. "Validity of a Squash-Specific Fitness Test." International Journal of Sports Physiology and Performance 4, no. 1 (2009): 29–40. http://dx.doi.org/10.1123/ijspp.4.1.29.

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Purpose:This study examined the validity of a squash-specific test designed to assess endurance capability and aerobic power.Methods:Eight squash players and eight runners performed, in a counterbalanced order, incremental treadmill (TT) and squash-specific (ST) tests to volitional exhaustion. Breath-by-breath oxygen uptake was determined by a portable analyzer and heart rate was assessed telemetrically. Time to exhaustion was recorded.Results:Independent t tests revealed longer time to exhaustion for squash players on the ST than runners (775 ± 103 vs. 607 ± 81 s; P = .003) but no difference between squash players and runners in maximal oxygen uptake ( Vo2max) or maximum heart rate (HRmax). Runners exercised longer on the TT (521 ± 135 vs. 343 ± 115 s; P = .01) and achieved higher Vo2max than squash players (58.6 ± 7.5 vs. 49.6 ± 7.3 mL·kg−1·min−1; P = .03), with no group difference in HRmax. Paired t tests showed squash players achieved higher Vo2max on the ST than the TT (52.2 ± 7.1 vs. 49.6 ± 7.3 mL·kg−1·min−1; P = .02). The Vo2max and HRmax of runners did not differ between tests, nor did the HRmax of squash players. ST and TT Vo2max correlated highly in squash players and runners (r = .94, P < .001; r = .88, P = .003).Conclusions:The ST discriminated endurance performance between squash players and runners and elicited higher Vo2max in squash players than a nonspecifc test. The results suggest that the ST is a valid assessment of Vo2max and endurance capability in squash players.

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Wilkinson, Michael, Damon Leedale-Brown, and Edward M. Winter. "Reproducibility of Physiological and Performance Measures from a Squash-Specific Fitness Test." International Journal of Sports Physiology and Performance 4, no. 1 (2009): 41–53. http://dx.doi.org/10.1123/ijspp.4.1.41.

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Purpose:We examined the reproducibility of performance and physiological responses on a squash-specific incremental test.Methods:Eight trained squash players habituated to procedures with two prior visits performed an incremental squash test to volitional exhaustion on two occasions 7 days apart. Breath-by-breath oxygen uptake ( Vo2) and heart rate were determined continuously using a portable telemetric system. Blood lactate concentration at the end of 4-min stages was assessed to determine lactate threshold. Once threshold was determined, test speed was increased every minute until volitional exhaustion for assessment of maximal oxygen uptake (Vo2max), maximum heart rate (HRmax), and performance time. Economy was taken as the 60-s mean of Vo2 in the final minute of the fourth stage (below lactate threshold for all participants). Typical error of measurement (TEM) with associated 90% confidence intervals, limits of agreement, paired sample t tests, and least products regression were used to assess the reproducibility of scores.Results:Performance time (TEM 27 s, 4%, 90% CI 19 to 49 s) Vo2max (TEM 2.4 mL·kg−1·min−1, 4.7%, 90% CI 1.7 to 4.3 mL·kg−1·min−1), maximum heart rate (TEM 2 beats·min−1, 1.3%, 90% CI 2 to 4 beats·min−1), and economy (TEM 1.6 mL·kg−1·min−1, 4.1%, 90% CI 1.1 to 2.8 mL·kg−1·min−1) were reproducible.Conclusions:The results suggest that endurance performance and physiological responses to a squash-specific fitness test are reproducible.

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Marsden, Islay D., Sandra E. Shumway, and Dianna K. Padilla. "Does size matter? The effects of body size and declining oxygen tension on oxygen uptake in gastropods." Journal of the Marine Biological Association of the United Kingdom 92, no. 7 (2011): 1603–17. http://dx.doi.org/10.1017/s0025315411001512.

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Metabolic rate is one of the most frequently measured physiological variables and the relationship between oxygen uptake and body mass is one of the most controversial issues in biology. The present study used closed chamber respirometry to compare the oxygen uptake of 32 species of benthic British gastropod molluscs of a wide size-range (from less than 0.001 g to greater than 10 g dry tissue weight). We investigated the effects of body size on the respiratory rate at 10°C to explore the evolutionary and phylogenetically determined patterns of metabolic scaling both among different gastropods groups, and within siphonate and asiphonate caenogastropods. Resting oxygen uptake (O2) increased with body mass (W) with a slope value of 0.6 using both ordinary least squares (OLS) and standard major axis (SMA) where N = 488, over a 6 fold range of body mass. The slopes b of the regression lines relating oxygen uptake to body mass were similar for all heterobranch molluscs and most caenogastropods. Highest mass-specific rates for oxygen consumption were found for the smallest littorinid species. Trophic mode significantly affected the amount of oxygen consumed with higher oxygen uptake in herbivores than other groups, including detritivores and predators. All of the gastropods reduced their oxygen consumption when exposed to declining oxygen conditions; however, about a third of the species exhibited partial regulation at higher oxygen partial pressures. When exposed to 20% normal saturation levels, smaller gastropods respired at approximately 25% of their rates in fully saturated seawater whereas larger species (above 0.1 g dry tissue weight) respired at approximately 35% of the values recorded at full saturation. Our study suggests that a scaling exponent relating O2 to body mass of 0.6 is typical and may be ‘universal’ for gastropods. It is below the 0.75 scaling exponent which has been proposed for ectothermic invertebrates. It is concluded that size does matter in determining the metabolic patterns of gastropods and that the quantity of oxygen consumed and the energy balance of gastropods is affected by activity, food type and exposure to declining oxygen conditions.

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Garcia-Ochoa, Felix, Sebastian Escobar, and Emilio Gomez. "Specific oxygen uptake rate as indicator of cell response of Rhodococcus erythropolis cultures to shear effects." Chemical Engineering Science 122 (January 2015): 491–99. http://dx.doi.org/10.1016/j.ces.2014.10.016.

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Mungkarndee, P., S. M. Rao Bhamidimarri, A. J. Mawson, and R. Chong. "Influence of changing microbial sludge characteristics on the degradation of an inhibitory compound." Water Science and Technology 31, no. 9 (1995): 55–60. http://dx.doi.org/10.2166/wst.1995.0344.

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The biodegradation of 2,4-dichlorophenoxyacetic acid (2,4-D) by a mixed microbial consortium enriched from soil was investigated. The specific oxygen uptake rate (SOUR) as a measure of biomass was found to be inappropriate as the characteristics and composition of the mixed culture were found to change significantly as the operating conditions changed. Both SOUR and biomass measurements revealed an expected substrate inhibition pattern up to around 1000 mg/L 2,4-D in batch incubation trials. The maximum growth rate was recorded at a substrate concentration of around 300 mg/L when the biomass was measured by gravimetrically, although maximum oxygen uptake activity was at a substrate concentration of 500 mg/L. The continuous experiments showed that 2,4-D can be degraded at inlet concentrations of up to 6362 mg/L resulting in &gt;99.5% degradation. The flocculation characteristics of the biomass were found to change as the substrate concentration changed and a microscopic examination confirmed that the changes in SOUR and specific substrate utilisation rate (SSUR) in the continuous system were due to changes in microbial culture characteristics.

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31

Miyatake, Fumihito, and Kazunori Iwabuchi. "Effect of compost temperature on oxygen uptake rate, specific growth rate and enzymatic activity of microorganisms in dairy cattle manure." Bioresource Technology 97, no. 7 (2006): 961–65. http://dx.doi.org/10.1016/j.biortech.2005.04.035.

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32

Gikas, P., and A. G. Livingston. "Use of Specific ATP Concentration and Specific Oxygen Uptake Rate to Determine Parameters of a Structured Model of Biomass Growth." Enzyme and Microbial Technology 22, no. 6 (1998): 500–510. http://dx.doi.org/10.1016/s0141-0229(97)00242-1.

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Bryce, JH, and JT Wiskich. "Effect of NAD and Rotenone on the Partitioning of Malate Oxidation Between Malate Dehydrogenase and Malic Enzyme in Isolated Plant Mitochondria." Functional Plant Biology 12, no. 3 (1985): 229. http://dx.doi.org/10.1071/pp9850229.

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Our aim was to determine whether there is a specific link between NAD-malic enzyme and the rotenone- insensitive bypass of electron transport. Mitochondria were isolated from fresh beetroot tissue, aged beetroot slices, and turnips. Oxygen uptake and pyruvate production were measured in reactions where these mitochondria were metabolizing malate at pH 6.8 in the presence of glutamate, to facilitate the removal of oxaloacetate, and in its absence. In the absence of glutamate there was substantial activity of malic enzyme. NAD+ (577 �M) prevented a fall in oxygen uptake by stimulating malic enzyme. Rotenone (19 �M) reduced oxygen uptake. This inhibited rate was stimulated by NAD+ due, in particular, to a stimulation of malic enzyme. We conclude that the stimulation of malate metabolism by NAD+ is accounted for by malic enzyme due to the unfavourable equilibrium of malate dehydrogenase for malate oxidation and the resultant accumulation of oxaloacetate, and not to any specific link between malic enzyme and the rotenone-insensitive bypass. In the presence of glutamate, malate dehydrogenase was the predominant malate metabolizing enzyme. Oxygen uptake and malic enzyme were stimulated and inhibited by NAD+ and rotenone, respectively. In the presence of rotenone, NAD+ stimulated oxygen uptake and increased the percentage due to malic enzyme. This stimulation is accounted for by the higher Kin of the rotenone-insensitive dehydrogenase for NADH and the unfavourable equilibrium position of malate dehydrogenase resulting in activation of malic enzyme only. We conclude that malic enzyme is not specifically linked to the rotenone-insensitive pathway of electron transport. This has important implications for the regulation of energy metabolism in plants.

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Third, K. A., S. Sepramaniam, Z. Tonkovic, M. Newland, and R. Cord-Ruwisch. "Optimisation of storage driven denitrification by using on-line specific oxygen uptake rate monitoring during SND in a SBR." Water Science and Technology 50, no. 10 (2004): 171–80. http://dx.doi.org/10.2166/wst.2004.0637.

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This study builds on previous experience of maximising the formation of COD as poly-hydroxybutyrate (PHB) and now describes a feedback technique of preserving the use of PHB for denitrification resulting in enhanced nitrogen removal rather than allowing its wasteful oxidation by oxygen. The feedback technique uses on-line SOUR monitoring for detecting the end-point of nitrification and controlling the aerobic phase length accordingly. The laboratory SBR was operated such that all organic substrate (acetate) was rapidly converted to PHB, which then served as the electron donor for nitrogen removal via simultaneous nitrification and denitrification (SND) during the aerobic phase (up to 70% SND). During SBR cycling with a fixed aeration length (240 minutes), PHB was unnecessarily oxidised after ammonium depletion, resulting in little denitrification and poor total nitrogen removal (69%). However, when the aerobic phase length was controlled via the SOUR, up to 1.8 CmM PHB (58 mg L−1 COD) could be preserved, enabling improved total nitrogen removal (86%). The drop in the SOUR after ammonium depletion was a reproducible event that could be detected even when using raw wastewater and fresh activated sludge. The SOUR-control technique holds promise to build up PHB over a number of SBR cycles. While advanced oxygen-control is used for improved N-removal in several existing WWTPs, this study investigates the importance of oxygen control with relevance to PHB driven SND in sequencing batch reactors.

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Nian Chen, Mark R. Bowles, and Susan M. Pond. "Prevention of Paraquat Toxicity in Suspensions of Alveolar Type II Cells by Paraquat-Specific Antibodies." Human & Experimental Toxicology 13, no. 8 (1994): 551–57. http://dx.doi.org/10.1177/096032719401300808.

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1 The herbicide, paraquat, is accumulated by the energy-dependent polyamine uptake pathway of alveolar type II cells. There it undergoes redox cycling that results in an amplified production of toxic reactive oxygen species and depletion of NADPH and other reducing equivalents. These processes account for the lung being the major target organ for paraquat toxicity. 2 We postulated that paraquat-specific antibodies would inhibit the uptake of the herbicide by type II cells and prevent its toxicity. Accordingly, we examined the effects of paraquat-specific monoclonal antibodies and Fab fragments on the uptake, efflux and cytotoxicity of 50 μM paraquat in suspensions of alveolar type II cells isolated from the rat. 3 The uptake of paraquat was linear over 40 min. Over this time, the uptake rate was inhibited significantly (% inhibition, 73-89) by IgG (25 or 50 μM) or Fab fragments (50 or 100 μM). 4 The apparent efflux rate of paraquat, studied over 16 h, was increased significantly from 0.12 h-1 for the control cells in medium to 0.17 h-1 by paraquat-specific Fab fragments but was unaffected by the specific IgG. 5 Cytotoxicity was determined by measuring the release of 51Cr from the cells. The cytotoxicity of 50 μM paraquat was decreased significantly (percent decrease, 56-80%) in the presence of specific antibodies. 6 These studies in vitro suggest some potential for immunotherapy in selected cases of paraquat poisoning.

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Converti, Attilio, Patrizia Perego, and Marco Del Borghi. "Effect of specific oxygen uptake rate onEnterobacter aerogenes energetics: Carbon and reduction degree balances in batch cultivations." Biotechnology and Bioengineering 82, no. 3 (2003): 370–77. http://dx.doi.org/10.1002/bit.10570.

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Krausch, Niels, Lucas Kaspersetz, Rogelio Diego Gaytán-Castro, et al. "Model-Based Characterization of E. coli Strains with Impaired Glucose Uptake." Bioengineering 10, no. 7 (2023): 808. http://dx.doi.org/10.3390/bioengineering10070808.

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The bacterium Escherichia coli is a widely used organism in biotechnology. For high space-time yields, glucose-limited fed-batch technology is the industry standard; this is because an overflow metabolism of acetate occurs at high glucose concentrations. As an interesting alternative, various strains with limited glucose uptake have been developed. However, these have not yet been characterized under process conditions. To demonstrate the efficiency of our previously developed high-throughput robotic platform, in the present work, we characterized three different exemplary E. coli knockout (KO) strains with limited glucose uptake capacities at three different scales (microtiter plates, 10 mL bioreactor system and 100 mL bioreactor system) under excess glucose conditions with different initial glucose concentrations. The extensive measurements of growth behavior, substrate consumption, respiration, and overflow metabolism were then used to determine the appropriate growth parameters using a mechanistic mathematical model, which allowed for a comprehensive comparative analysis of the strains. The analysis was performed coherently with these different reactor configurations and the results could be successfully transferred from one platform to another. Single and double KO mutants showed reduced specific rates for substrate uptake qSmax and acetate production qApmax; meanwhile, higher glucose concentrations had adverse effects on the biomass yield coefficient YXSem. Additional parameters compared to previous studies for the oxygen uptake rate and carbon dioxide production rate indicated differences in the specific oxygen uptake rate qOmax. This study is an example of how automated robotic equipment, together with mathematical model-based approaches, can be successfully used to characterize strains and obtain comprehensive information more quickly, with a trade-off between throughput and analytical capacity.

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38

McKenzie, D. J., E. Cataldi, P. Romano, S. F. Owen, E. W. Taylor, and P. Bronzi. "Effects of acclimation to brackish water on the growth, respiratory metabolism, and swimming performance of young-of-the-year Adriatic sturgeon (Acipenser naccarii)." Canadian Journal of Fisheries and Aquatic Sciences 58, no. 6 (2001): 1104–12. http://dx.doi.org/10.1139/f01-059.

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Specific growth rates, exercise respirometry, and swimming performance were compared in young-of-the-year Adriatic sturgeon (Acipenser naccarii) maintained in freshwater (FW) or acclimated to brackish water (BW) that was slightly hypertonic to sturgeon plasma, at a salinity of 11 g·L1. Specific growth rate was significantly (17%) lower in BW than in FW. Sturgeon in BW also had a significantly (30%) higher standard metabolic rate than those in FW. In both groups, the relationship between swimming speed and oxygen uptake was described equally well by a linear or exponential equation, with a power relationship between swimming speed and net cost of locomotion and a linear relationship between tailbeat frequency and swimming speed. However, sturgeon in BW exhibited higher mean total oxygen uptake, net costs, and tailbeat frequencies than the FW group at any given swimming speed. There were, however, no differences in aerobic scope or maximum sustainable swimming speed between the FW and BW groups because the BW group exhibited a compensatory increase in active metabolic rate and maximum tailbeat frequency. The results indicate that FW is a more suitable environment than mildly hypertonic BW for young-of-the-year Adriatic sturgeon.

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39

Anpilogov, Igor, and Pavel Pavlov. "Similarities and dissimilarities in response to specific submaximal aerobic exercise in newcomer and well-trained athletes." BIO Web of Conferences 26 (2020): 00066. http://dx.doi.org/10.1051/bioconf/20202600066.

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The study was aimed on evaluation the applicability of certain distinct characteristics of heart rate dynamics dependence upon physical training load as criteria of young athletes functional fitness. Nine elite adult canoe and kayak rowers and twenty five young skiers aged 11-13 took part in the research program. Canoe and kayak rowers performed incremental tests on a rowing simulator (4*1000 m). The following parameters were measured: heart rate, oxygen heart rate, breath frequency, respiratory exchange ratio, oxygen uptake, and minute ventilation. Young skiers performed moderate run on a stadium track maintaining constant speed to voluntary physical exhaustion. Comparison of the trends in young and elite athletes allows assuming that the response to the given load on the third segment of the test exceeded the current level of fitness and continuation of the exercise at this level can cause overstrain and overtraining. It has to be pointed out that this assumption requires further research with measurement of a broader range of parameters.

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Hughson, Richard L. "Oxygen uptake kinetics: historical perspective and future directions." Applied Physiology, Nutrition, and Metabolism 34, no. 5 (2009): 840–50. http://dx.doi.org/10.1139/h09-088.

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Oxygen uptake has been studied in the transitions between rest and exercise for more than 100 years, yet the mechanisms regulating the rate of increase in oxidative metabolism remain controversial. Some of the controversy is a consequence of incorrect interpretations of kinetic parameters describing amplitude and time constant relationships, whereas other factors relate to an incomplete framework for interpretation of experimental results. In this review, a new conceptual 3-dimensional model is proposed to explore the intracellular environment of skeletal muscle in the rest-to-exercise transition. The model incorporates the so-called “metabolic inertia” describing the increases in metabolic substrates and enzyme activation, along with the dynamic changes in intracellular partial pressure of oxygen (PO2). Considerable evidence exists during normal submaximal exercise challenges for an effect of changes in O2 delivery to working muscles affecting the intracellular PO2 (displayed on the x axis) and the high energy phosphate concentration (y axis) during steady-state exercise as well as the transitions from rest to exercise. The z axis incorporates a hypothetical description of metabolic inertia that is enhanced by increased enzyme activation and production of metabolic substrates. Specific examples are given that describe how this axis can affect oxygen uptake kinetics within the context of changing intracellular PO2 and energetic states. Oxidative metabolism at the onset of exercise is regulated by a dynamic balance of O2 transport and utilization mechanisms and is not limited solely by metabolic inertia.

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Wang, Rong Chang, Shu Peng Si, Dian Hai Yang, and Jian Fu Zhao. "Comparison of A²/O and Membrane Bioreactor Processes for Municipal Wastewater Treatment: Nutrient Removal Performance and Sludge Characteristics." Advanced Materials Research 356-360 (October 2011): 1647–54. http://dx.doi.org/10.4028/www.scientific.net/amr.356-360.1647.

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The performance of nitrogen and phosphorus removal was investigated in pilot-scale A2/O, A2/O-MBR and mA2/O-MBR processes for treating municipal wastewater. The results show that these processes had a similar COD and ammonia removal efficiency, but A2/O process had better denitrification efficiency than MBR processes. In order to explain the difference of nitrogen and phosphorus removal performance in the investigated processes, specific oxygen uptake rate (SOUR), specific denitrification rate (SDNR), anaerobic release rate and anoxic and aerobic uptake rate of the activated sludge taken from A2/O and mA2/O-MBR processes were compared. The results show that the activated sludge of mA2/O-MBR process had a higher nitrifying activity in aerobic tank than A2/O process, the denitrifying activity in anoxic tanks were roughly equal and A2/O process had a higher denitrifying phosphorus removal activity in anoxic tank than mA2/O-MBR process.

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42

Rivera, Chantal A., Blair U. Bradford, Vitor Seabra, and Ronald G. Thurman. "Role of endotoxin in the hypermetabolic state after acute ethanol exposure." American Journal of Physiology-Gastrointestinal and Liver Physiology 275, no. 6 (1998): G1252—G1258. http://dx.doi.org/10.1152/ajpgi.1998.275.6.g1252.

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This study investigated the role of endotoxin in the hypermetabolic state or swift increase in alcohol metabolism (SIAM) due to acute ethanol exposure. Female Sprague-Dawley rats (100–120 g) were given ethanol (5 g/kg) by gavage. Endotoxin measured in plasma from portal blood was not detectable in saline-treated controls; however, 90 min after ethanol, endotoxin was increased to 85 ± 14 pg/ml, and endotoxin clearance was diminished by ∼50%. Oxygen uptake in perfused livers was increased 48% by ethanol, and production of PGE2 by isolated Kupffer cells was increased similarly. These effects were blunted by elimination of gram-negative bacteria and endotoxin with antibiotics before ethanol administration. To reproduce ethanol-induced endotoxemia, endotoxin was infused via the mesenteric vein at a rate of 2 ng ⋅ kg−1 ⋅ h−1. Endotoxin mimicked the effect of ethanol on oxygen uptake. The specific Kupffer cell toxicant GdCl3completely prevented increases in oxygen uptake due to endotoxin. These findings demonstrate that endotoxin plays a pivotal role in SIAM, most likely by stimulating eicosanoid release from Kupffer cells.

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43

Herrera-Valenzuela, Tomás, Emerson Franchini, Pablo Valdés-Badilla, et al. "Relation between VT1, VT2, and VO2max with the Special Wrestling Fitness Test in Youth Wrestlers: A Short Report." International Journal of Environmental Research and Public Health 20, no. 3 (2023): 2570. http://dx.doi.org/10.3390/ijerph20032570.

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This study investigated the relationship between peak oxygen uptake and ventilatory threshold 1 (VT1) and 2 (VT2) with the Special Wrestling Fitness Test variables. Thirteen wrestlers (male: six; female: seven) of Olympic freestyle wrestling were assessed. The Pearson’s correlation coefficient (p < 0.05) was used to establish the relationship between variables. A positive correlation was found between VT1 with throws in set B (r = 0.77; p = 0.002; 95%CI = 0.37–0.93), total throws (r = 0.73; p = 0.004; 95%CI = 0.30–0.91), heart rate recovery (r = 0.58; p = 0.036; 95%CI = 0.05–0.86), and test index (r = −0.60; p = 0.031; 95%CI = −0.86–0.07); between VT2 and throws in set B (r = 0.57; p = 0.043; 95%CI = 0.01–0.86); and between peak oxygen uptake with throws in set B (r = 0.77; p = 0.002; 95%CI = 0.39–0.93), throws in set C (r = 0.64; p = 0.02; 95%CI = 0.12–0.89), and total throws (r = 0.72; p = 0.006; 95%CI = 0.28–0.91). In conclusion, the peak oxygen uptake and ventilatory thresholds correlated with specific Special Wrestling Fitness Test variables.

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Zamouche-Zerdazi, R., M. Bencheikh Lehocine, and A. H. Meniai. "Influence of Endogenous OUR Determination on the KLa$${K_L}a$$, Exogenous OUR, Total Oxygen Consumption and Heterotrophic Yield in a Completely Mixed Batch Reactor." International Journal of Chemical Reactor Engineering 12, no. 2 (2014): 695–704. http://dx.doi.org/10.1515/ijcre-2014-0069.

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Abstract In wastewater treatment, waste removal and biomass activity are important processes which need to be monitored for a good process control. The difficulties in the interpretation of the total COD, BOD and VSS measurements encouraged the development of respirometric methods for assessing the kinetic constants. Respirometry is an important technique in assessing biological reaction in wastewater treatment. $${K_L}a$$, depends on endogenous oxygen uptake rate (OURend), is a key constant in evaluating respirogram-specific parameters. Generally, OURend is assumed constant in the dissolved oxygen equations. However, it is not the case. Consequently, this paper deals with the influence of OURend calculations region on $${K_L}a$$ determination, exogenous oxygen uptake rate (OURexo), total oxygen consumption and heterotrophic yield (YH). It was shown that the value of OURend and $${K_L}a$$ varied considerably, a maximum of 56%, depending on where to consider Cfin, on the oxygen concentration variation curve. Even though, the variation on OURend and $${K_L}a$$ is important its influence on Yo/x and YH is attenuated to 7.5% and 6%, respectively. This may be due to the local nature of the first parameters (OURend and $${K_L}a$$) and the global nature of the later ones. Moreover, this can be seen through the variation of the calculated amount of oxygen consumed (QThete) which is of the order 7.6%.

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Bergeron, Janique, and Michael Paice. "Monitoring of Activated Sludge Systems Using a Combination of Specific Oxygen Uptake Rates and Specific Adenosine Triphosphate Measurements." Water Quality Research Journal 36, no. 4 (2001): 659–85. http://dx.doi.org/10.2166/wqrj.2001.035.

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Abstract Two five-litre activated sludge (AS) bioreactors were operated for several months to demonstrate potential mill applications of a four-assay set, which has been proposed as a tool for monitoring the health of the AS microbial population. The set consists of three specific oxygen uptake rate (SOUR) determinations at different substrate concentrations (SOURat, SOURnmax and SOURtox where at, nmax and tox are defined as aeration tank, near maximum, and toxic, respectively), and a specific adenosine triphosphate (SATP) assay. Two disturbances were applied at different times to an AS system treating kraft effluent. First, temperature was increased from 25 to 40°C, and second, a black liquor spill was simulated. The data before, during, and after these disturbances were statistically analyzed. From this analysis, we concluded that the four-assay set could be used as a microbial health characterization (MHC) tool. It allows an operator to correlate microbial changes with operating data over a mediumterm time scale. We compared the values obtained during periods of upset in the system treating the kraft effluent, to the baseline data set determined from stable operation periods. This demonstrated how the four-assay set could be used as a biological early warning (BEW) tool. It allows a treatment system operator to make appropriate adjustments immediately after detecting values that fall outside the baseline data range.

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Schaeffer, P., K. Conley, and S. Lindstedt. "Structural correlates of speed and endurance in skeletal muscle: the rattlesnake tailshaker muscle." Journal of Experimental Biology 199, no. 2 (1996): 351–58. http://dx.doi.org/10.1242/jeb.199.2.351.

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The western diamondback rattlesnake Crotalus atrox can rattle its tail continuously for hours at frequencies approaching 90 Hz. We examined the basis of these fast sustainable contractions using electromyography, data on oxygen uptake and the quantitative ultrastructure of the tailshaker muscle complex. The tailshaker muscle has no apparent unique structures; rather, the relative proportions of the structures common to all skeletal muscles appear to be present (1) to minimize activation, contraction and relaxation times via an extremely high volume density of sarcoplasmic reticulum (26 %) as well as, (2) to maximize ATP resysnthesis via a high volume density of mitochondria (26 %). The high rate of ATP supply is reflected in the in vivo muscle mass-specific oxygen uptake of this group of muscles which, at 585 ml O2 kg-1 min-1 during rattling at 30 &deg;C body temperature, exceeds that reported for other ectotherm and many endotherm muscles. Since the change in oxygen uptake paralleled that of the rattling frequency over the range of measured body temperatures, there was a nearly constant O2 cost per muscle contraction (0.139&plusmn;0.016 &micro;l O2 g-1). Electromyo-graphic analysis suggests that each of the six muscles that make up the shaker complex may be a single motor unit. Finally, the maximum rate of mitochondrial oxygen uptake is similar to that of various mammals, a hummingbird, a lizard, an anuran amphibian and of isolated mitochondria (at 10 000-40 000 molecules O2 s-1 &micro;m2 of cristae surface area, when normalized to 30 &deg;C), suggesting a shared principle of design of the inner mitochondrial membrane among the vertebrates.

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Dandanell, Sune, Anne-Marie Elbe, Gertrud Pfister, Peter Elsborg, and Jørn W Helge. "Relationship between volition, physical activity and weight loss maintenance: Study rationale, design, methods and baseline characteristics." Scandinavian Journal of Public Health 45, no. 3 (2016): 299–304. http://dx.doi.org/10.1177/1403494816682378.

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Aims: To investigate the relationship between volition, physical activity and weight loss maintenance. Methods: We recruited 84 sedentary (maximal oxygen uptake: 25 ± 5 ml/min), overweight and obese (Body mass index (BMI) 38 ± 7 m/h2, fat 44 ± 7 %) women ( n = 55) and men ( n = 29) for an interdisciplinary prospective study with follow-up. The change in lifestyle and weight loss is promoted via a 3-month intensive lifestyle intervention at a private health school. The intervention consists of supervised training (1–3 hours/day), a healthy hypo-caloric diet (−500 to −700 kCal/day) and education in healthy lifestyle in classes/groups. The participants’ body weight and composition (Dual Energy X-ray absorptiometry), volitional skills (questionnaire), physical activity level (heart rate accelerometer/questionnaire) and maximal oxygen uptake (indirect calorimetry) are to be monitored before, after, and 3 and 12 months after the intervention. Results: At the 12-month follow-up, three different groups will be established: Clinical weight loss maintenance (> 10% weight loss from baseline), moderate weight loss maintenance (1–10% weight loss) and no weight loss (or weight regain). A linear mixed model analysis will be used to compare levels of volitional skills, physical activity and maximal oxygen uptake over time, between the three groups. Correlational analyses will be used to investigate possible associations between volition, maximal oxygen uptake, physical activity level and weight loss maintenance. Conclusions: If specific volitional skills are identified as predictors of adherence to physical activity and success in clinical weight loss maintenance, these can be trained in future intensive lifestyle interventions in order to optimize the success rate.

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Wong, W. K., and D. W. Smith. "Evaluation of an on‐line specific oxygen uptake rate monitoring apparatus at the gold bar wastewater treatment plant." Environmental Technology 13, no. 1 (1992): 45–54. http://dx.doi.org/10.1080/09593339209385127.

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Khursheed, Anwar, Meena Kumari Sharma, Vinay Kumar Tyagi, Abid Ali Khan, and A. A. Kazmi. "Specific oxygen uptake rate gradient – Another possible cause of excess sludge reduction in oxic-settling-anaerobic (OSA) process." Chemical Engineering Journal 281 (December 2015): 613–22. http://dx.doi.org/10.1016/j.cej.2015.06.105.

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Kim, Kong Sik, Young Je Yoo, and Min Hong Kim. "Control of intracellular ammonium level using specific oxygen uptake rate for overproduction of citric acid by Aspergillus niger." Journal of Fermentation and Bioengineering 79, no. 6 (1995): 555–59. http://dx.doi.org/10.1016/0922-338x(95)94747-f.

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Journal articles on the topic 'Specific oxygen uptake rate'

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