Oxygen uptake under starvation and short periods of sudden temperature change was measured forlarval herring (Clupea harengus L.) reared at average temperature of 7.3, 11 and 12.9℃. Larval stagesbetween first feedi...Oxygen uptake under starvation and short periods of sudden temperature change was measured forlarval herring (Clupea harengus L.) reared at average temperature of 7.3, 11 and 12.9℃. Larval stagesbetween first feeding and premetamorphosis were used. For comparison, the routine oxygen uptake(ROU) was also investigated and followed the relationship Q=0.974+0. 174 tW<sup>0.210</sup>, where Q is in μg/(mg·h), W is dry body weight in mg and t is temperature in ℃. The oxygen uptake under starvation(SOU, deprived of food for 24 h) was different from the routine when the larval dry weightwas less than 0.6-0.8 mg, it increased with temperature and body weight giving the reationship Q=1.568+0.110 tW<sup>0.380</sup>, if the larval dry weight mp more than 0.6-0.8 mg, it reverted to the norm(Q=1.704+0.078 tW<sup>-0.349</sup>). The oxygen uptake was tested in short periods (3 h) of sudden temperaturechanges in six groups: 7.3 to 11, 7.3 to 12.9, 11 to 7.3. 11 to 12.9, 12.9 to 7.3 and 1.29 to11℃. The oxygen uptake in the 7.3 to 12.9 and展开更多
The nitrogen uptake, yield and its components for two super-high-yielding hybrid rice combinations, Guodao 6 and Eryou 7954 were investigated under different plant densities (15, 18, and 21 plants/m^2) and different...The nitrogen uptake, yield and its components for two super-high-yielding hybrid rice combinations, Guodao 6 and Eryou 7954 were investigated under different plant densities (15, 18, and 21 plants/m^2) and different nitrogen application rates (120, 150, 180, and 210 kg/hm^2). The experiment was conducted on loam soil during 2004-2006 at the experimental farm of the China National Rice Research Institute in Hangzhou, China. In these years, the two hybrid rice cleady showed higher yield at a plant density of 15 plants/m^2 with a nitrogen application rate of 180 kg/hm^2. Guodao 6 produced an average grain yield of 10 215.6 kg/hm^2 across the three years, while the yield of Eryou 7954 was 9 633.0 kg/hm^2. With fewer plants per unit-area and larger plants in the plots, the two hybrid rice produced more panicles per plant in three years. The highest nitrogen uptake of the two hybrid rice was at a plant density of 15 plants/m^2 with a nitrogen application rate of 180 kg/hm^2. Further increasing nitrogen application rate was not advantageous for nitrogen uptake in super-high-yielding rice under the same plant density.展开更多
The rates of oxygen consumption, tolerance of hypoxia and desiccation of the Chinese black sleeper ( Bostrichthys sinensis) and mudskipper (Boleophthalmus pectinirostris) embryos were investigated. The pattern of ...The rates of oxygen consumption, tolerance of hypoxia and desiccation of the Chinese black sleeper ( Bostrichthys sinensis) and mudskipper (Boleophthalmus pectinirostris) embryos were investigated. The pattern of oxygen consumption of the Chinese black sleeper embryos was similar to that of the mudskipper ones. The lowest rates of oxygen consumption [ ( 1.65 ±0. 66) nmol/ (ind. ·h) ] of the Chinese black sleeper embryos 16 h after fertilization and the lowest rates of oxygen consumption [ (0.79± 0.08 )nmolf( ind. · h) ] of the mudskipper embryos 6 h after fertilization were recorded, respectively. Then the rates of oxygen consumption of these two species embryos increased gradually until hatching [ (8.26 ± 1.70 ) nmolf( ind.· h) in the Chinese black sleeper, (2.69 ± 0.23 )nmolf( ind. · h) in mudskipper]. After exposure to hypoxia water (0.16 mg/dm^3), bradycardia of the embryos occurred in both the Chinese black sleeper and the mudskipper. However, the Chinese black sleeper embryos survived approximately 45 min longer than the mudskipper ones. After exposure to desiccation at a relative humidity of 58%, bradycardia of the embryos was observed in both the Chinese black sleeper and the mudskipper, and the Chinese black sleeper embryos lived approximately 9 min longer than the mudskipper ones.展开更多
temperature and the diasolved oxygen content affect the oxygen consumption of juveniles of Chinese prawn (Penaeus chinensis), giant tiger prawn (P. monodon) and giant freshwater prawn(Macrobrachium rosenbergii). There...temperature and the diasolved oxygen content affect the oxygen consumption of juveniles of Chinese prawn (Penaeus chinensis), giant tiger prawn (P. monodon) and giant freshwater prawn(Macrobrachium rosenbergii). There is good correlation between the oxygen consumption rate (V, mg/g·h) of the above three prawn species and the water temperature, and dissolved oxygen. In the range of test temperature, V increased with water temperature and diassolved oxygen content. The V of the above three prawn species increased 0.085 mg/g·h, 0. 093 mg/g·h and 0. 08 mg/g·h respectively with each ℃ of rising temperature. The comatose point and stifling point of the juveniles rose obviously at unsuitable temperature.展开更多
The large water-pumping and particle-capturing gills of the filter-feeding blue mussel Mytilus edulis are oversized for respiratory purposes. Consequently, the oxygen uptake rate of the mussel has been suggested to be...The large water-pumping and particle-capturing gills of the filter-feeding blue mussel Mytilus edulis are oversized for respiratory purposes. Consequently, the oxygen uptake rate of the mussel has been suggested to be rather insensitive to decreasing oxygen concentrations in the ambient water, since the diffusion rate of oxygen from water flowing through the mussel determines oxygen uptake. We tested this hypothesis by measuring the oxygen uptake in mussels exposed to various oxygen concentrations. These concentrations were established via N2-bubbling of the water in a respiration chamber with mussels fed algal cells to stimulate fully opening of the valves. It was found that mussels exposecl to oxygen concentrations decreasing from 9 to 2 mg O2/L resulted in a slow but significant reduction in the respiration rate, while the filtration rate remained high and constant. Thus, a decrease of oxygen concentration by 78% only resulted in a 25% decrease in respiration rate. However, at oxygen concentrations below 2 mg O2/L M. edulis responded by gradually closing its valves, resulting in a rapid decrease of filtration rate, concurrent with a rapid reduction of respiration rate. These observations indicated that M. edulis is no longer able to maintain its normal aerobic metabolism at oxygen concentration below 2 mg O2/L, and there seems to be an energy-saving mechanism in bivalve molluscs to strongly reduce their activity when exposed to low oxygen conditions.展开更多
The impact of water temperature(24, 27, 30 and 33℃) and salinity(15, 20, 25, 30 and 33) on oxygen consumption(OCR) and ammonium excretion rate(AER) of ♀ Epinephelus fuscoguttatus ×♂ E. lanceolatus hybrid group...The impact of water temperature(24, 27, 30 and 33℃) and salinity(15, 20, 25, 30 and 33) on oxygen consumption(OCR) and ammonium excretion rate(AER) of ♀ Epinephelus fuscoguttatus ×♂ E. lanceolatus hybrid grouper juveniles(9.39 ± 0.07 g) were investigated under the fed and un-fed conditions. The results showed that the OCR and AER were significantly(P < 0.05) affected by temperature and salinity under both fed and un-fed conditions. When temperature was 24–33℃, the OCR and AER of fed hybrid grouper juveniles were 85.68%–129.52% and 125.78%–287.63%, respectively, higher than those of un-fed hybrid grouper juveniles. The O/N ratio, protein use(P_u), Q_(10)(respiration) and Q_(10)(excretion) of fed hybrid grouper juveniles were 14.43–24.01, 28.35% – 48.48%, 1.69 and 3.01, respectively. The O/N ratio, P_u, Q_(10)(respiration), Q_(10)(excretion) of un-fed hybrid grouper juveniles were 20.39 – 31.79, 22.16% – 34.34%, 1.23 and 1.17, respectively. When salinity was 15–33, the OCR and AER of fed hybrid grouper juveniles increased by 87.42% – 116.85% and 215.38% – 353.57%, respectively, over those of un-fed hybrid grouper juveniles. The O/N ratio and P_u of fed hybrid grouper juveniles were 14.48 – 17.78, 39.36% – 49.43%, respectively. The O/N ratio and Pu of un-fed hybrid grouper juveniles were 20.39 – 31.79 and 22.16% – 34.34%, respectively. The specific dynamic action(SDA) of hybrid grouper juveniles was mainly related to protein metabolism. The results had a guiding significance to the large-scale intensive aquaculture of hybrid grouper juveniles.展开更多
The supply of highly concentrated oxygen positively affects cognitive processing in normal young adults. However, there have been few reports on changes in cognitive ability in elderly subjects following highly concen...The supply of highly concentrated oxygen positively affects cognitive processing in normal young adults. However, there have been few reports on changes in cognitive ability in elderly subjects following highly concentrated oxygen administration. This study investigated changes in cognitive ability, blood oxygen saturation (%), and heart rate (beats/min) in normal elderly subjects at three different levels of oxygen [21% (1 L/min), 93% (1 L/min), and 93% (5 L/min)] administered during a 1-back task. Eight elderly male (75.3 + 4.3 years old) and 10 female (71.1 + 3.9 years old) subjects, who were normal in cognitive ability as shown by a score of more than 24 points in the Mini-Mental State Examination-Korea, participated in the experiment. The experiment consisted of an adaptation phase after the start of oxygen administration (3 minutes), a control phase to obtain stable baseline measurements of heart rate and blood oxygen saturation before the task (2 minutes) and a task phase during which the 1-back task was performed (2 minutes). Three levels of oxygen were administered throughout the three phases (7 minutes). Blood oxygen saturation and heart rate were measured during each phase. Our results show that blood oxygen saturation increased, heart rate decreased, and response time in the 1-back task decreased as the concentration and amount of administered oxygen increased. This shows that administration of sufficient oxygen for optimal cognitive functioning increases blood oxygen saturation and decreases heart rate.展开更多
Surgical treatments of acute myocardial infarction (MI) possess a high clinical effectiveness, but there are fixed limitations, related to the patient’s state, which are limited by medical resources and organizationa...Surgical treatments of acute myocardial infarction (MI) possess a high clinical effectiveness, but there are fixed limitations, related to the patient’s state, which are limited by medical resources and organizational problems. The development of new medical technologies provides a better and effective non-surgical treatment of acute MI and increases long-term prognosis in this category of patients. The study aims to investigate the influence of hyperbaric oxygenation treatment on clinical outcomes (survival rate and recurrent myocardial infarction (rMI)) during the five-year period of monitoring. The study involved 697 patients who suffered from acute MI, having undergone the standard treatment. The patients were randomly divided into two groups: Group 1 (reference, n = 363);Group 2 (test, n = 334). Patients of Group 2 were given the traditional treatment, accompanied with HBOT (isopression for forty minutes at a working pressure of 0.03 MPa). HBOT was applied first through the fifth day following MI. The treatment course included six cycles, once per day. The clinical assessment was focused on clinical outcome: rMI and mortality related to cardiovascular events. HBOT application that accompanied the acute MI with traditional pharmacotherapy has been proved to reduce rMI within five years following inpatient discharge (rMI rate was 14% in the reference group and 5.4% in the test group, χ2 = 13.3, р < 0.05). The combination of HBOT with traditional methods in treating acute MI makes it possible to raise the five-year survival rate from 84.4% up to 95.9%.展开更多
Background Submaximal oxygen uptake measures are more feasible and may better predict clinical cardiac outcomes than maximal tests in older adults with heart failure (HF). We examined relationships between maximal o...Background Submaximal oxygen uptake measures are more feasible and may better predict clinical cardiac outcomes than maximal tests in older adults with heart failure (HF). We examined relationships between maximal oxygen uptake, submaximal oxygen kinetics, fianctional mobility, and physical activity in older adults with HF and reduced ejection fraction. Methods Older adults with HF and reduced ejection fraction (n = 25, age 75 :i: 7 years) were compared to 25 healthy ageand gender-matched controls. Assessments included a maximal treadmill test for peak oxygen uptake (VO2p^ak), oxygen uptake kinetics at onset of and on recovery from a submaximal treadmill test, functional mobility testing [Get Up and Go (GUG), Comfortable Gait Speed (CGS), Unipedal Stance (US)], and self-reported physical activity (PA). Results Compared to controls, HF had worse performance on GUG, CGS, and US, greater delays in submaximal oxygen uptake kinetics, and lower PA. In controls, VO2peak was more strongly associated with functional mobility and PA than submaximal oxygen uptake kinetics. In HF patients, submaximal oxygen uptake kinetics were similarly associated with GUG and CGS as VO2peak, but weakly associated with PA. Conclusions Based on their mobility performance, older HF patients with reduced ejection fraction are at risk for adverse functional outcomes. In this population, submaximal oxygen uptake measures may be equivalent to VO2 peak in predicting functional mobility, and in addition to being more feasible, may provide better insight into how aerobic function relates to mobility in older adults with HF.展开更多
Based on heat and mass transfer characteristics of spontaneous combustion of coal,Arrhenius equation and the Ranz-Marshall correlation,a novel approach was proposed in this paper to estimate oxygen consumption rate of...Based on heat and mass transfer characteristics of spontaneous combustion of coal,Arrhenius equation and the Ranz-Marshall correlation,a novel approach was proposed in this paper to estimate oxygen consumption rate of self-ignition of coal at high temperature.Compared with the conventional methods,this approach involves not only kinetic properties of self-ignition of coal and temperature,but also the ambient air flow characteristics and diameter of coal particle.To testify the proposed approach,oxygen consumption rates at high temperature were measured by the programmable isothermal oven experiments.Comparisons between experimental and theoretical results indicate that the rates of oxygen depletion calculated by the proposed approach agree well with those measured from laboratory-scale experiments,which further validates the proposed approach.展开更多
Knowledge of oxygen consumption rates and asphyxiation points in fish is important to determine appropriate stocking and water quality management in aquaculture. The oxygen consumption rate and asphyxiation point in C...Knowledge of oxygen consumption rates and asphyxiation points in fish is important to determine appropriate stocking and water quality management in aquaculture. The oxygen consumption rate and asphyxiation point in Chanodichthys mongolicus were detected under laboratory conditions using an improved respirometer chamber. The results revealed that more accurate estimates can be obtained by adjusting the volume of the respirometer chamber, which may avoid system errors caused by either repeatedly adjusting fish density or selecting different equipment specifications. The oxygen consumption rate and asphyxiation point of C. mongolicus increased with increasing water temperature and decreasing fish size. Changes in the C. mongolicus oxygen consumption rate were divided into three stages at water temperatures of 11-33~C: (I) a low temperature oxygen consumption rate stage when water temperature was 11-19~C, (2) the optimum temperature oxygen consumption rate stage when water temperature was 19-23~C, and (3) a high temperature oxygen consumption rate stage when water temperature was 〉27~C. The temperature quotients (Q10) obtained suggested that C. mongolicus preferred a temperature range of 19-23~C. At 19~C, C. mongolicus exhibited higher oxygen consumption rates during the day when the maximum values were observed at 10:00 and 14:00 than at night when the minimum occurred at 02:00.展开更多
Oxygen consumption is a fundamental component of metabolic networks, mitochondrial function, and global carbon cycling. To date there is no method available that allows for replicate measurements on attached and unatt...Oxygen consumption is a fundamental component of metabolic networks, mitochondrial function, and global carbon cycling. To date there is no method available that allows for replicate measurements on attached and unattached biological samples without compensation for extraneous oxygen leaking into the system. Here we present the Respiratory Detection System, which is compatible with virtually any biological sample. The RDS can be used to measure oxygen uptake in microliter-scale volumes with a reversibly sealed sample chamber, which contains a porphyrin-based oxygen sensor. With the RDS, one can maintain a diffusional seal for up to three hours, allowing for the direct measurement of respiratory function of samples with fast or slow metabolic rates. The ability to easily measure oxygen uptake in small volumes with small populations or dilute samples has implications in cell biology, environmental biology, and clinical diagnostics.展开更多
The influence of different cooling rates on the morphology and oxygen permeabilityr of polypropylene containing ferrocene has been investigated. The spherulitic crystalline size and structure, which can affect the oxy...The influence of different cooling rates on the morphology and oxygen permeabilityr of polypropylene containing ferrocene has been investigated. The spherulitic crystalline size and structure, which can affect the oxygen permeability are dependent upon the heating temperature, annealing time and cooling rate. The modulus of the composite was measured b}' dynamic mechanical analysis.展开更多
In a preceding work we have reported experiments showing that an hydroalcoholic exctract of Agaricus blazei is able to exert purinergic effects in the isolated perfused rat liver when it is infused into the portal vei...In a preceding work we have reported experiments showing that an hydroalcoholic exctract of Agaricus blazei is able to exert purinergic effects in the isolated perfused rat liver when it is infused into the portal vein in monovascular perfusion (entry: portal vein;exit: hepatic vein). In the present communication we are presenting and discussing experiments done with the bivascularly perfused rat liver (entry: portal vein + hepatic artery;exit: hepatic vein) in order to verify if the hemodynamic effects also occur in the arterial bed. It was found that the A. blazei extract is also active when infused into the hepatic arterial bed, with differences in both sensitivity and nature of the effects on either perfusion pressure or oxygen consumption. Constriction of the arterial bed required much higher concentrations of the extract than the portal bed. The kinetics of the response was also different, with a biphasic instead of a monophasic response. These results provide a promising starting point for future studies aiming to bring to light more mechanistic details about these and possibly other effects.展开更多
The link between cigarette smoking and predicted oxygen uptake was investigated using data for 149 Japanese men not taking medication. Cigarette smoking habits were obtained through interviews by well-trained staff. T...The link between cigarette smoking and predicted oxygen uptake was investigated using data for 149 Japanese men not taking medication. Cigarette smoking habits were obtained through interviews by well-trained staff. The influence of cigarette smoking on predicted oxygen uptake, predicted work rate and predicted heart rate were evaluated. Predicted oxygen uptake decreased with age. Predicted oxygen uptake and predicted work rate in men who smoked cigarettes was significantly lower than in subjects who did not, after adjusting for age. The differences in parameters did not reach significant levels after adjusting for age and physical activity evaluated by Σ[metabolic equivalents × h per week (METs?h/w)] (predicted oxygen uptake: p = 0.0632, predicted work rate: p = 0.0873). Cigarette smoking might be a modifyable factor for improving the aerobic exercise level in Japanese men.展开更多
Instead of the energy-intensive Haber-Bosch process,the researchers proposed a way to produce ammonia using water and nitrogen as feedstock,powered by electricity,without polluting the environment.Nevertheless,how to ...Instead of the energy-intensive Haber-Bosch process,the researchers proposed a way to produce ammonia using water and nitrogen as feedstock,powered by electricity,without polluting the environment.Nevertheless,how to design efficient electrocatalyst for electrocatalytic nitrogen reduction reaction(NRR)is still urgent and challenging.Herein,a strategy is proposed to adjust the morphology and surface electronic structure of electrocatalyst by optimizing material synthesis method.LiNbO3(lithium niobate,LN)cubes with oxygen-rich vacancy and regular morphology were synthesized by hydrothermal synthesis and followed molten salt calcination process,which were used for electrocatalytic NRR under mild conditions.Compared with LN nanoparticles synthesized by solid phase reaction,LN cubes exhibit better NRR performance,with the highest ammonia yield rate(13.74μg.h^(-1).mg^(-1))at the best potential of-0.45V(vs.reversible hydrogen electrode,RHE)and the best Faradaic efficiency(85.43%)at-0.4 V.Moreover,LN cubes electrocatalyst also demonstrates high stability in 7 cycles and 18 h current-time tests.Further investigation of the reaction mechanism confirmed that the structure of oxygen vacancy could adjust the electronic structure of the electrocatalyst,which was conducive to the adsorption and activation of N_(2) molecule and also increased the ECSA of electrocatalyst,thus providing more active sites for the NRR process.展开更多
The grey system theory, with the characteristics of fewer modeling data and higher accuracy, was employed to model the batch dyeing process for the purpose of accurate online control. The GM(1, 1) and GM (0, N) mo...The grey system theory, with the characteristics of fewer modeling data and higher accuracy, was employed to model the batch dyeing process for the purpose of accurate online control. The GM(1, 1) and GM (0, N) models of the grey system theory were discussed for their feasibilities of modding for batch dyeing process. The combination of direct dyestuff Fast Red F3B on cotton was chosen as a representative of the common dyeing method for describing the modeling process. Firstly, the GM( 1, 1 ) model and the GM(1, 1) combined with GM(0, N) model were employed to model the equilibrium percentage of dyeing uptake rate. Secondly, an integrated dyeing uptake rate model with three factors ( temperature, salt concentration, and pH) was established based on the adsorption rate equation. Experimental results show that this model has higher accuracy and beetler generalization ability, which can predict the results of batch dyeing process. Due to the application of grey system theory, the model has a lot of advantages, such as being easy to determine the parameter value and small amount of calculation. So it can also be suitable for the same type of combination of dyestuff-fahric by changing the parameters value only.展开更多
Purpose: To investigate the link between peak oxygen uptake and regional body composition by dual energy X-ray absorptiometry (DEXA) in Japanese subjects. Methods: A total of 93 men (42.2 ± 12.3 years old) ...Purpose: To investigate the link between peak oxygen uptake and regional body composition by dual energy X-ray absorptiometry (DEXA) in Japanese subjects. Methods: A total of 93 men (42.2 ± 12.3 years old) and 106 women (43.5 ± 12.3 years old) were enrolled in this cross-sectional investigation study. Peak oxygen uptake was measured by the breath-by-breath method. Regional body composition i.e., body fat mass, lean body mass, and body fat percentage was evaluated using DEXA. In addition, metabolic risk parameters were also evaluated. Results: Peak oxygen uptake was 37.6± 8.7 mL/kg/min in men and 31.1 ± 6.4 mL/kg/min in women, and decreased with age in both genders. Peak oxygen uptake was significantly correlated with total body fat percentage (men: r = -0.684, p 〈 0.0001; women: r = -0.681, p 〈 0.0001). These associations remained even after adjusting for age and total lean body mass. However, peak work rate was positively and significantly correlated with leg lean body mass. Conclusion: Peak oxygen uptake was closely correlated with total body fat percentage in both genders. Aerobic exercise as well as leg resistance training might be useful for improving peak oxygen uptake in Japanese subjects. Copyright展开更多
This paper concerns the influence of temperature and local concentration of oxygen on the conversion efficiency of carbon into CO, CO2, CH4, C3H8, C2H4, C2H2, C2H6, C6H6, during the thermal degradation of plastic bags...This paper concerns the influence of temperature and local concentration of oxygen on the conversion efficiency of carbon into CO, CO2, CH4, C3H8, C2H4, C2H2, C2H6, C6H6, during the thermal degradation of plastic bags and millet stalks. The experimental device used is the tubular kiln, coupled to an analyzer Fourier Transform Infrared (FTIR) and a Non Dispersive Infrared analyzer (NDIR). Temperatures are considered between 800 and 1000°C. Local concentrations of oxygen during thermal degradation are 0%, 10% and 21%. On the one hand results obtained on the influence of temperature show that for each type of thermal degradation and whatever the temperature of the combustion, the rate of conversion of carbon remains substantially the same. In the case of plastic bags, the rate of carbon converted during pyrolysis is about 90% of carbon converted during reductive combustion. On the other hand, with millet stalks, the carbon converted represents only 60% of the rate of carbon converted during combustion to 10% oxygen. 1 to 2% of carbon not analyzed is in the form of aromatic compounds that are found most often in the soot and/or tar from this combustion system. Moreover, whatever the temperature, the overall efficiency of carbon conversion increases linearly with the local concentration of oxygen. During the thermal degradation of plastic bags, we see that the reducer environment has fostered the conversion of 7% of carbon more while the presence of oxygen in double proportion promotes the conversion of 27% carbon. Regarding the influence of the local content of oxygen, it is clear that for plastic bags, the reactions of oxidation of CO into CO2 tend to be favored for the benefit of those of hydrocarbons into CO. The formation of CO and CO2 by oxidation of light hydrocarbons is primarily from gaseous compounds CH4 and C2H4. At 950°C, we have also acetylene (C2H2) which is involved in the production of carbon oxides. At 1000°C, benzene (C6H6) heavily involved in the formation of CO and CO2. However, with millet stalks, more the local content of oxygen increases, more combustion is better, that is to say that the oxidation reactions producing CO2 are faster than the oxidation reactions of hydrocarbons into CO. The rate of carbon converted into CO and CO2 is higher for millet stalks than for plastic bags, due to this oxygen levels higher in millet stalks than in plastic bags. Similarly, for the millet stalks, from pyrolysis to combustion (at 10 and 21% oxygen), there is practically no hydrocarbon emitted.展开更多
文摘Oxygen uptake under starvation and short periods of sudden temperature change was measured forlarval herring (Clupea harengus L.) reared at average temperature of 7.3, 11 and 12.9℃. Larval stagesbetween first feeding and premetamorphosis were used. For comparison, the routine oxygen uptake(ROU) was also investigated and followed the relationship Q=0.974+0. 174 tW<sup>0.210</sup>, where Q is in μg/(mg·h), W is dry body weight in mg and t is temperature in ℃. The oxygen uptake under starvation(SOU, deprived of food for 24 h) was different from the routine when the larval dry weightwas less than 0.6-0.8 mg, it increased with temperature and body weight giving the reationship Q=1.568+0.110 tW<sup>0.380</sup>, if the larval dry weight mp more than 0.6-0.8 mg, it reverted to the norm(Q=1.704+0.078 tW<sup>-0.349</sup>). The oxygen uptake was tested in short periods (3 h) of sudden temperaturechanges in six groups: 7.3 to 11, 7.3 to 12.9, 11 to 7.3. 11 to 12.9, 12.9 to 7.3 and 1.29 to11℃. The oxygen uptake in the 7.3 to 12.9 and
基金supported by the Ministry of Agriculture of China(Grant No.2005-2009)
文摘The nitrogen uptake, yield and its components for two super-high-yielding hybrid rice combinations, Guodao 6 and Eryou 7954 were investigated under different plant densities (15, 18, and 21 plants/m^2) and different nitrogen application rates (120, 150, 180, and 210 kg/hm^2). The experiment was conducted on loam soil during 2004-2006 at the experimental farm of the China National Rice Research Institute in Hangzhou, China. In these years, the two hybrid rice cleady showed higher yield at a plant density of 15 plants/m^2 with a nitrogen application rate of 180 kg/hm^2. Guodao 6 produced an average grain yield of 10 215.6 kg/hm^2 across the three years, while the yield of Eryou 7954 was 9 633.0 kg/hm^2. With fewer plants per unit-area and larger plants in the plots, the two hybrid rice produced more panicles per plant in three years. The highest nitrogen uptake of the two hybrid rice was at a plant density of 15 plants/m^2 with a nitrogen application rate of 180 kg/hm^2. Further increasing nitrogen application rate was not advantageous for nitrogen uptake in super-high-yielding rice under the same plant density.
基金supported by the National Natural Science Foundation of China under contract No.40476056the Science and Technology Key Project of Fujian Province of China under contract Nos 2003N026 and 2004SZ01-02.
文摘The rates of oxygen consumption, tolerance of hypoxia and desiccation of the Chinese black sleeper ( Bostrichthys sinensis) and mudskipper (Boleophthalmus pectinirostris) embryos were investigated. The pattern of oxygen consumption of the Chinese black sleeper embryos was similar to that of the mudskipper ones. The lowest rates of oxygen consumption [ ( 1.65 ±0. 66) nmol/ (ind. ·h) ] of the Chinese black sleeper embryos 16 h after fertilization and the lowest rates of oxygen consumption [ (0.79± 0.08 )nmolf( ind. · h) ] of the mudskipper embryos 6 h after fertilization were recorded, respectively. Then the rates of oxygen consumption of these two species embryos increased gradually until hatching [ (8.26 ± 1.70 ) nmolf( ind.· h) in the Chinese black sleeper, (2.69 ± 0.23 )nmolf( ind. · h) in mudskipper]. After exposure to hypoxia water (0.16 mg/dm^3), bradycardia of the embryos occurred in both the Chinese black sleeper and the mudskipper. However, the Chinese black sleeper embryos survived approximately 45 min longer than the mudskipper ones. After exposure to desiccation at a relative humidity of 58%, bradycardia of the embryos was observed in both the Chinese black sleeper and the mudskipper, and the Chinese black sleeper embryos lived approximately 9 min longer than the mudskipper ones.
文摘temperature and the diasolved oxygen content affect the oxygen consumption of juveniles of Chinese prawn (Penaeus chinensis), giant tiger prawn (P. monodon) and giant freshwater prawn(Macrobrachium rosenbergii). There is good correlation between the oxygen consumption rate (V, mg/g·h) of the above three prawn species and the water temperature, and dissolved oxygen. In the range of test temperature, V increased with water temperature and diassolved oxygen content. The V of the above three prawn species increased 0.085 mg/g·h, 0. 093 mg/g·h and 0. 08 mg/g·h respectively with each ℃ of rising temperature. The comatose point and stifling point of the juveniles rose obviously at unsuitable temperature.
基金Supported by the Special Scientific Research Funds for Central Non-profit Institutes,Chinese Academy of Fishery Sciences(No.2016HY-ZD0102)
文摘The large water-pumping and particle-capturing gills of the filter-feeding blue mussel Mytilus edulis are oversized for respiratory purposes. Consequently, the oxygen uptake rate of the mussel has been suggested to be rather insensitive to decreasing oxygen concentrations in the ambient water, since the diffusion rate of oxygen from water flowing through the mussel determines oxygen uptake. We tested this hypothesis by measuring the oxygen uptake in mussels exposed to various oxygen concentrations. These concentrations were established via N2-bubbling of the water in a respiration chamber with mussels fed algal cells to stimulate fully opening of the valves. It was found that mussels exposecl to oxygen concentrations decreasing from 9 to 2 mg O2/L resulted in a slow but significant reduction in the respiration rate, while the filtration rate remained high and constant. Thus, a decrease of oxygen concentration by 78% only resulted in a 25% decrease in respiration rate. However, at oxygen concentrations below 2 mg O2/L M. edulis responded by gradually closing its valves, resulting in a rapid decrease of filtration rate, concurrent with a rapid reduction of respiration rate. These observations indicated that M. edulis is no longer able to maintain its normal aerobic metabolism at oxygen concentration below 2 mg O2/L, and there seems to be an energy-saving mechanism in bivalve molluscs to strongly reduce their activity when exposed to low oxygen conditions.
基金supported by the project of National Science and Technology Supporting Plan (No. 2011BAD13B04)
文摘The impact of water temperature(24, 27, 30 and 33℃) and salinity(15, 20, 25, 30 and 33) on oxygen consumption(OCR) and ammonium excretion rate(AER) of ♀ Epinephelus fuscoguttatus ×♂ E. lanceolatus hybrid grouper juveniles(9.39 ± 0.07 g) were investigated under the fed and un-fed conditions. The results showed that the OCR and AER were significantly(P < 0.05) affected by temperature and salinity under both fed and un-fed conditions. When temperature was 24–33℃, the OCR and AER of fed hybrid grouper juveniles were 85.68%–129.52% and 125.78%–287.63%, respectively, higher than those of un-fed hybrid grouper juveniles. The O/N ratio, protein use(P_u), Q_(10)(respiration) and Q_(10)(excretion) of fed hybrid grouper juveniles were 14.43–24.01, 28.35% – 48.48%, 1.69 and 3.01, respectively. The O/N ratio, P_u, Q_(10)(respiration), Q_(10)(excretion) of un-fed hybrid grouper juveniles were 20.39 – 31.79, 22.16% – 34.34%, 1.23 and 1.17, respectively. When salinity was 15–33, the OCR and AER of fed hybrid grouper juveniles increased by 87.42% – 116.85% and 215.38% – 353.57%, respectively, over those of un-fed hybrid grouper juveniles. The O/N ratio and P_u of fed hybrid grouper juveniles were 14.48 – 17.78, 39.36% – 49.43%, respectively. The O/N ratio and Pu of un-fed hybrid grouper juveniles were 20.39 – 31.79 and 22.16% – 34.34%, respectively. The specific dynamic action(SDA) of hybrid grouper juveniles was mainly related to protein metabolism. The results had a guiding significance to the large-scale intensive aquaculture of hybrid grouper juveniles.
文摘The supply of highly concentrated oxygen positively affects cognitive processing in normal young adults. However, there have been few reports on changes in cognitive ability in elderly subjects following highly concentrated oxygen administration. This study investigated changes in cognitive ability, blood oxygen saturation (%), and heart rate (beats/min) in normal elderly subjects at three different levels of oxygen [21% (1 L/min), 93% (1 L/min), and 93% (5 L/min)] administered during a 1-back task. Eight elderly male (75.3 + 4.3 years old) and 10 female (71.1 + 3.9 years old) subjects, who were normal in cognitive ability as shown by a score of more than 24 points in the Mini-Mental State Examination-Korea, participated in the experiment. The experiment consisted of an adaptation phase after the start of oxygen administration (3 minutes), a control phase to obtain stable baseline measurements of heart rate and blood oxygen saturation before the task (2 minutes) and a task phase during which the 1-back task was performed (2 minutes). Three levels of oxygen were administered throughout the three phases (7 minutes). Blood oxygen saturation and heart rate were measured during each phase. Our results show that blood oxygen saturation increased, heart rate decreased, and response time in the 1-back task decreased as the concentration and amount of administered oxygen increased. This shows that administration of sufficient oxygen for optimal cognitive functioning increases blood oxygen saturation and decreases heart rate.
文摘Surgical treatments of acute myocardial infarction (MI) possess a high clinical effectiveness, but there are fixed limitations, related to the patient’s state, which are limited by medical resources and organizational problems. The development of new medical technologies provides a better and effective non-surgical treatment of acute MI and increases long-term prognosis in this category of patients. The study aims to investigate the influence of hyperbaric oxygenation treatment on clinical outcomes (survival rate and recurrent myocardial infarction (rMI)) during the five-year period of monitoring. The study involved 697 patients who suffered from acute MI, having undergone the standard treatment. The patients were randomly divided into two groups: Group 1 (reference, n = 363);Group 2 (test, n = 334). Patients of Group 2 were given the traditional treatment, accompanied with HBOT (isopression for forty minutes at a working pressure of 0.03 MPa). HBOT was applied first through the fifth day following MI. The treatment course included six cycles, once per day. The clinical assessment was focused on clinical outcome: rMI and mortality related to cardiovascular events. HBOT application that accompanied the acute MI with traditional pharmacotherapy has been proved to reduce rMI within five years following inpatient discharge (rMI rate was 14% in the reference group and 5.4% in the test group, χ2 = 13.3, р < 0.05). The combination of HBOT with traditional methods in treating acute MI makes it possible to raise the five-year survival rate from 84.4% up to 95.9%.
文摘Background Submaximal oxygen uptake measures are more feasible and may better predict clinical cardiac outcomes than maximal tests in older adults with heart failure (HF). We examined relationships between maximal oxygen uptake, submaximal oxygen kinetics, fianctional mobility, and physical activity in older adults with HF and reduced ejection fraction. Methods Older adults with HF and reduced ejection fraction (n = 25, age 75 :i: 7 years) were compared to 25 healthy ageand gender-matched controls. Assessments included a maximal treadmill test for peak oxygen uptake (VO2p^ak), oxygen uptake kinetics at onset of and on recovery from a submaximal treadmill test, functional mobility testing [Get Up and Go (GUG), Comfortable Gait Speed (CGS), Unipedal Stance (US)], and self-reported physical activity (PA). Results Compared to controls, HF had worse performance on GUG, CGS, and US, greater delays in submaximal oxygen uptake kinetics, and lower PA. In controls, VO2peak was more strongly associated with functional mobility and PA than submaximal oxygen uptake kinetics. In HF patients, submaximal oxygen uptake kinetics were similarly associated with GUG and CGS as VO2peak, but weakly associated with PA. Conclusions Based on their mobility performance, older HF patients with reduced ejection fraction are at risk for adverse functional outcomes. In this population, submaximal oxygen uptake measures may be equivalent to VO2 peak in predicting functional mobility, and in addition to being more feasible, may provide better insight into how aerobic function relates to mobility in older adults with HF.
基金Project(51534008) supported by the National Natural Science Foundation of China
文摘Based on heat and mass transfer characteristics of spontaneous combustion of coal,Arrhenius equation and the Ranz-Marshall correlation,a novel approach was proposed in this paper to estimate oxygen consumption rate of self-ignition of coal at high temperature.Compared with the conventional methods,this approach involves not only kinetic properties of self-ignition of coal and temperature,but also the ambient air flow characteristics and diameter of coal particle.To testify the proposed approach,oxygen consumption rates at high temperature were measured by the programmable isothermal oven experiments.Comparisons between experimental and theoretical results indicate that the rates of oxygen depletion calculated by the proposed approach agree well with those measured from laboratory-scale experiments,which further validates the proposed approach.
基金Supported by the Central-Level Non-Profit Scientific Research Institutes Special Funds(Nos.2014A07XK04,HSY201403)the Harbin Science and Technology Project(No.2012AA6CN037)the National Key Technology Research and Development Program of China(No.2012BAD25B09)
文摘Knowledge of oxygen consumption rates and asphyxiation points in fish is important to determine appropriate stocking and water quality management in aquaculture. The oxygen consumption rate and asphyxiation point in Chanodichthys mongolicus were detected under laboratory conditions using an improved respirometer chamber. The results revealed that more accurate estimates can be obtained by adjusting the volume of the respirometer chamber, which may avoid system errors caused by either repeatedly adjusting fish density or selecting different equipment specifications. The oxygen consumption rate and asphyxiation point of C. mongolicus increased with increasing water temperature and decreasing fish size. Changes in the C. mongolicus oxygen consumption rate were divided into three stages at water temperatures of 11-33~C: (I) a low temperature oxygen consumption rate stage when water temperature was 11-19~C, (2) the optimum temperature oxygen consumption rate stage when water temperature was 19-23~C, and (3) a high temperature oxygen consumption rate stage when water temperature was 〉27~C. The temperature quotients (Q10) obtained suggested that C. mongolicus preferred a temperature range of 19-23~C. At 19~C, C. mongolicus exhibited higher oxygen consumption rates during the day when the maximum values were observed at 10:00 and 14:00 than at night when the minimum occurred at 02:00.
文摘Oxygen consumption is a fundamental component of metabolic networks, mitochondrial function, and global carbon cycling. To date there is no method available that allows for replicate measurements on attached and unattached biological samples without compensation for extraneous oxygen leaking into the system. Here we present the Respiratory Detection System, which is compatible with virtually any biological sample. The RDS can be used to measure oxygen uptake in microliter-scale volumes with a reversibly sealed sample chamber, which contains a porphyrin-based oxygen sensor. With the RDS, one can maintain a diffusional seal for up to three hours, allowing for the direct measurement of respiratory function of samples with fast or slow metabolic rates. The ability to easily measure oxygen uptake in small volumes with small populations or dilute samples has implications in cell biology, environmental biology, and clinical diagnostics.
文摘The influence of different cooling rates on the morphology and oxygen permeabilityr of polypropylene containing ferrocene has been investigated. The spherulitic crystalline size and structure, which can affect the oxygen permeability are dependent upon the heating temperature, annealing time and cooling rate. The modulus of the composite was measured b}' dynamic mechanical analysis.
文摘In a preceding work we have reported experiments showing that an hydroalcoholic exctract of Agaricus blazei is able to exert purinergic effects in the isolated perfused rat liver when it is infused into the portal vein in monovascular perfusion (entry: portal vein;exit: hepatic vein). In the present communication we are presenting and discussing experiments done with the bivascularly perfused rat liver (entry: portal vein + hepatic artery;exit: hepatic vein) in order to verify if the hemodynamic effects also occur in the arterial bed. It was found that the A. blazei extract is also active when infused into the hepatic arterial bed, with differences in both sensitivity and nature of the effects on either perfusion pressure or oxygen consumption. Constriction of the arterial bed required much higher concentrations of the extract than the portal bed. The kinetics of the response was also different, with a biphasic instead of a monophasic response. These results provide a promising starting point for future studies aiming to bring to light more mechanistic details about these and possibly other effects.
文摘The link between cigarette smoking and predicted oxygen uptake was investigated using data for 149 Japanese men not taking medication. Cigarette smoking habits were obtained through interviews by well-trained staff. The influence of cigarette smoking on predicted oxygen uptake, predicted work rate and predicted heart rate were evaluated. Predicted oxygen uptake decreased with age. Predicted oxygen uptake and predicted work rate in men who smoked cigarettes was significantly lower than in subjects who did not, after adjusting for age. The differences in parameters did not reach significant levels after adjusting for age and physical activity evaluated by Σ[metabolic equivalents × h per week (METs?h/w)] (predicted oxygen uptake: p = 0.0632, predicted work rate: p = 0.0873). Cigarette smoking might be a modifyable factor for improving the aerobic exercise level in Japanese men.
基金the financial support from the National Natural Science Foundation of China(22075196,21878204)Key Research and Development Program of Shanxi Province(International Cooperation,201903D421073)Research Project Supported by Shanxi Scholarship Council of China(2022-050).
文摘Instead of the energy-intensive Haber-Bosch process,the researchers proposed a way to produce ammonia using water and nitrogen as feedstock,powered by electricity,without polluting the environment.Nevertheless,how to design efficient electrocatalyst for electrocatalytic nitrogen reduction reaction(NRR)is still urgent and challenging.Herein,a strategy is proposed to adjust the morphology and surface electronic structure of electrocatalyst by optimizing material synthesis method.LiNbO3(lithium niobate,LN)cubes with oxygen-rich vacancy and regular morphology were synthesized by hydrothermal synthesis and followed molten salt calcination process,which were used for electrocatalytic NRR under mild conditions.Compared with LN nanoparticles synthesized by solid phase reaction,LN cubes exhibit better NRR performance,with the highest ammonia yield rate(13.74μg.h^(-1).mg^(-1))at the best potential of-0.45V(vs.reversible hydrogen electrode,RHE)and the best Faradaic efficiency(85.43%)at-0.4 V.Moreover,LN cubes electrocatalyst also demonstrates high stability in 7 cycles and 18 h current-time tests.Further investigation of the reaction mechanism confirmed that the structure of oxygen vacancy could adjust the electronic structure of the electrocatalyst,which was conducive to the adsorption and activation of N_(2) molecule and also increased the ECSA of electrocatalyst,thus providing more active sites for the NRR process.
基金National Natural Science Foundation of China(No.61074154)
文摘The grey system theory, with the characteristics of fewer modeling data and higher accuracy, was employed to model the batch dyeing process for the purpose of accurate online control. The GM(1, 1) and GM (0, N) models of the grey system theory were discussed for their feasibilities of modding for batch dyeing process. The combination of direct dyestuff Fast Red F3B on cotton was chosen as a representative of the common dyeing method for describing the modeling process. Firstly, the GM( 1, 1 ) model and the GM(1, 1) combined with GM(0, N) model were employed to model the equilibrium percentage of dyeing uptake rate. Secondly, an integrated dyeing uptake rate model with three factors ( temperature, salt concentration, and pH) was established based on the adsorption rate equation. Experimental results show that this model has higher accuracy and beetler generalization ability, which can predict the results of batch dyeing process. Due to the application of grey system theory, the model has a lot of advantages, such as being easy to determine the parameter value and small amount of calculation. So it can also be suitable for the same type of combination of dyestuff-fahric by changing the parameters value only.
基金supported in part by Research Grants from the Ministry of Health,Labour,and Welfare of Japan
文摘Purpose: To investigate the link between peak oxygen uptake and regional body composition by dual energy X-ray absorptiometry (DEXA) in Japanese subjects. Methods: A total of 93 men (42.2 ± 12.3 years old) and 106 women (43.5 ± 12.3 years old) were enrolled in this cross-sectional investigation study. Peak oxygen uptake was measured by the breath-by-breath method. Regional body composition i.e., body fat mass, lean body mass, and body fat percentage was evaluated using DEXA. In addition, metabolic risk parameters were also evaluated. Results: Peak oxygen uptake was 37.6± 8.7 mL/kg/min in men and 31.1 ± 6.4 mL/kg/min in women, and decreased with age in both genders. Peak oxygen uptake was significantly correlated with total body fat percentage (men: r = -0.684, p 〈 0.0001; women: r = -0.681, p 〈 0.0001). These associations remained even after adjusting for age and total lean body mass. However, peak work rate was positively and significantly correlated with leg lean body mass. Conclusion: Peak oxygen uptake was closely correlated with total body fat percentage in both genders. Aerobic exercise as well as leg resistance training might be useful for improving peak oxygen uptake in Japanese subjects. Copyright
文摘This paper concerns the influence of temperature and local concentration of oxygen on the conversion efficiency of carbon into CO, CO2, CH4, C3H8, C2H4, C2H2, C2H6, C6H6, during the thermal degradation of plastic bags and millet stalks. The experimental device used is the tubular kiln, coupled to an analyzer Fourier Transform Infrared (FTIR) and a Non Dispersive Infrared analyzer (NDIR). Temperatures are considered between 800 and 1000°C. Local concentrations of oxygen during thermal degradation are 0%, 10% and 21%. On the one hand results obtained on the influence of temperature show that for each type of thermal degradation and whatever the temperature of the combustion, the rate of conversion of carbon remains substantially the same. In the case of plastic bags, the rate of carbon converted during pyrolysis is about 90% of carbon converted during reductive combustion. On the other hand, with millet stalks, the carbon converted represents only 60% of the rate of carbon converted during combustion to 10% oxygen. 1 to 2% of carbon not analyzed is in the form of aromatic compounds that are found most often in the soot and/or tar from this combustion system. Moreover, whatever the temperature, the overall efficiency of carbon conversion increases linearly with the local concentration of oxygen. During the thermal degradation of plastic bags, we see that the reducer environment has fostered the conversion of 7% of carbon more while the presence of oxygen in double proportion promotes the conversion of 27% carbon. Regarding the influence of the local content of oxygen, it is clear that for plastic bags, the reactions of oxidation of CO into CO2 tend to be favored for the benefit of those of hydrocarbons into CO. The formation of CO and CO2 by oxidation of light hydrocarbons is primarily from gaseous compounds CH4 and C2H4. At 950°C, we have also acetylene (C2H2) which is involved in the production of carbon oxides. At 1000°C, benzene (C6H6) heavily involved in the formation of CO and CO2. However, with millet stalks, more the local content of oxygen increases, more combustion is better, that is to say that the oxidation reactions producing CO2 are faster than the oxidation reactions of hydrocarbons into CO. The rate of carbon converted into CO and CO2 is higher for millet stalks than for plastic bags, due to this oxygen levels higher in millet stalks than in plastic bags. Similarly, for the millet stalks, from pyrolysis to combustion (at 10 and 21% oxygen), there is practically no hydrocarbon emitted.