Individual variation in metabolic traits of wild nine-banded armadillos(Dasypus novemcinctus), and the aerobic capacity model for the evolution of endothermy

2002 ◽  
Vol 205 (20) ◽  
pp. 3207-3214 ◽  
Author(s):  
Patrice Boily
Keyword(s):  
Aerobic Capacity ◽  
General Pattern ◽  
Metabolic Rates ◽  
Dasypus Novemcinctus ◽  
Functional Link ◽  
Metabolic Traits ◽  
Capacity Model ◽  
Coefficients Of Variation ◽  
Selection For ◽  
Predicted Values

SUMMARYA fundamental assumption of the aerobic capacity model for the evolution of endothermy is that basal (BMR) and peak (PMR) metabolic rates are functionally linked at the intraspecific level. The purpose of this study was to use the nine-banded armadillo Dasypus novemcinctus as a model to test this assumption. Measurements of BMR, PMR, mass and rectal temperature were obtained over two summers from wild, adult individuals from a population in Louisiana, USA. BMR and PMR were positively correlated (r=0.62), and both were significantly higher (by 46% for BMR and by 35% for PMR) in 1999 than in 1998. Similar results were obtained whether metabolic rates were expressed in whole-animal or mass-independent units. These results suggest the existence of a functional link between BMR and PMR and are therefore consistent with the aerobic capacity model. In addition, this study confirmed that, compared with most eutherian mammals, the nine-banded armadillo exhibits low and highly variable basal and peak metabolic rates (20-60% the predicted values; 23% and 27% coefficients of variation) and rectal temperatures (range 32.7-35.3°C). Such metabolic traits are, however, consistent with the general pattern previously observed for other members of the order Xenarthra and with the hypothesis that low metabolic rates in armored mammals evolved as a result of unbalanced selection in which, because of low predation risks,selection for a high aerobic capacity was much weaker than the opposing selection for energy conservation.

scholarly journals Intraspecific Correlations of Basal and Maximal Metabolic Rates in Birds and the Aerobic Capacity Model for the Evolution of Endothermy

PLoS ONE ◽  
2012 ◽  
Vol 7 (3) ◽  
pp. e34271 ◽  
Author(s):  
David L. Swanson ◽  
Nathan E. Thomas ◽  
Eric T. Liknes ◽  
Sheldon J. Cooper
Keyword(s):  
Aerobic Capacity ◽  
Metabolic Rates ◽  
Capacity Model

Evolution, atmospheric oxygen, and complex disease

2007 ◽  
Vol 30 (3) ◽  
pp. 205-208 ◽  
Author(s):  
Lauren Gerard Koch ◽  
Steven L. Britton
Keyword(s):  
Energy Transfer ◽  
Aerobic Capacity ◽  
Large Scale ◽  
Complex Disease ◽  
Atmospheric Oxygen ◽  
General Pattern ◽  
Oxygen Metabolism ◽  
Network Analyses ◽  
Optimal Capacity ◽  
Selection For

If evolution is an accurate statement of our biology, then disease must be tightly associated with its patterns. We considered selection for more optimal capacity for energy transfer as the most general pattern of evolution. From this, we propose that the etiology of complex disease is linked tightly to the evolutionary transition to cellular complexity that was afforded by the steep thermodynamic gradient of an oxygen atmosphere. In accord with this thesis, clinical studies reveal a strong statistical link between low aerobic capacity and all-cause mortality. In addition, large-scale unbiased network analyses demonstrate the pivotal role of oxygen metabolism in cellular function. The demonstration that multiple disease risks segregated during two-way artificial selection for low and high aerobic capacity in rats provides a remote test of these possible connections between evolution, oxygen metabolism, and complex disease. Even more broadly, an atmosphere with oxygen may be uniquely essential for development of complex life anywhere because oxygen is stable as a diatomic gas, is easily transported, and has a high electronegativity for participation in energy transfer via redox reactions.

Multiple Sclerosis: Treadmill Versus Cycle Ergometry Maximal Exercise Test Responses

2020 ◽  
Vol 9 (3) ◽  
pp. 113-117
Author(s):  
Garett Griffith ◽  
Badeia Saed ◽  
Tracy Baynard
Keyword(s):  
Multiple Sclerosis ◽  
Aerobic Capacity ◽  
Work Capacity ◽  
Cross Sectional Study ◽  
Cycle Ergometer ◽  
Cycle Ergometry ◽  
Cross Sectional ◽  
Complete Test ◽  
Peak Aerobic Capacity ◽  
Predicted Values

ABSTRACT Background: Multiple sclerosis (MS) is an autoimmune disease that impacts the central nervous system. MS generally results in decreased mobility and work capacity. Our objective was to determine exercise testing responses on both a treadmill and cycle ergometer among individuals with MS who were able to ambulate freely. Methods: Twenty-six individuals with MS participated in a cross-sectional study (44 ± 11 years; body mass index 26.8 ± 6.2 kg·m−2; expanded disability scale score 3.1 ± 0.9), with 24 individuals with complete test data for both treadmill and cycle ergometry tests. Peak aerobic capacity (VO2peak) for both treadmill and cycle ergometry tests were measured with indirect calorimetry. Results: Participants safely completed both treadmill and cycle ergometry tests, and treadmill testing yielded higher values (26.7 ± 6.4 mL·kg−1·min−1) compared with cycle ergometry (23.7 ± 5.7 mL·kg−1·min−1), with values ~12% greater for treadmill. When comparing tests to their respected predicted values within modality, treadmill tests were 8% lower and cycle ergometry tests were 10% lower than predicted. Conclusions: While peak aerobic capacity was very low for this population, treadmill tests were still higher than cycle ergometry data, with this difference between modes being similar to that observed in healthy adult populations. Additional research is required to determine if these findings are impacted by participation in physical activity or regular exercise.

scholarly journals Metabolic traits in brown trout (Salmo trutta) vary in response to food restriction and intrinsic factors

2020 ◽  
Vol 8 (1) ◽  
Author(s):  
Louise C Archer ◽  
Stephen A Hutton ◽  
Luke Harman ◽  
W Russell Poole ◽  
Patrick Gargan ◽  
...  
Keyword(s):  
Life History ◽  
Metabolic Rate ◽  
Intraspecific Variation ◽  
Brown Trout ◽  
Environmental Conditions ◽  
Food Restriction ◽  
Metabolic Rates ◽  
Intrinsic Factors ◽  
Metabolic Traits ◽  
Food Conditions

Abstract Metabolic rates vary hugely within and between populations, yet we know relatively little about factors causing intraspecific variation. Since metabolic rate determines the energetic cost of life, uncovering these sources of variation is important to understand and forecast responses to environmental change. Moreover, few studies have examined factors causing intraspecific variation in metabolic flexibility. We explore how extrinsic environmental conditions and intrinsic factors contribute to variation in metabolic traits in brown trout, an iconic and polymorphic species that is threatened across much of its native range. We measured metabolic traits in offspring from two wild populations that naturally show life-history variation in migratory tactics (one anadromous, i.e. sea-migratory, one non-anadromous) that we reared under either optimal food or experimental conditions of long-term food restriction (lasting between 7 and 17 months). Both populations showed decreased standard metabolic rates (SMR—baseline energy requirements) under low food conditions. The anadromous population had higher maximum metabolic rate (MMR) than the non-anadromous population, and marginally higher SMR. The MMR difference was greater than SMR and consequently aerobic scope (AS) was higher in the anadromous population. MMR and AS were both higher in males than females. The anadromous population also had higher AS under low food compared to optimal food conditions, consistent with population-specific effects of food restriction on AS. Our results suggest different components of metabolic rate can vary in their response to environmental conditions, and according to intrinsic (population-background/sex) effects. Populations might further differ in their flexibility of metabolic traits, potentially due to intrinsic factors related to life history (e.g. migratory tactics). More comparisons of populations/individuals with divergent life histories will help to reveal this. Overall, our study suggests that incorporating an understanding of metabolic trait variation and flexibility and linking this to life history and demography will improve our ability to conserve populations experiencing global change.

Energy expenditure during load carriage at high altitude

1981 ◽  
Vol 51 (1) ◽  
pp. 14-18 ◽  
Author(s):  
A. Cymerman ◽  
K. B. Pandolf ◽  
A. J. Young ◽  
J. T. Maher
Keyword(s):  
Energy Expenditure ◽  
High Altitude ◽  
Sea Level ◽  
Prediction Equation ◽  
Cycle Ergometer ◽  
Load Carriage ◽  
Metabolic Rates ◽  
Specific Exercise ◽  
Upper Limit ◽  
Predicted Values

To determine the applicability of a prediction equation for energy expenditure during load carriage at high altitude that was previously validated at sea level, oxygen uptake (Vo2) was determined in five young men at 4,300 m while they walked with backpack loads of 0, 15, and 30 kg at treadmill grades of 0,8, and 16% at 1.12 m.s-1 for 10 min. Mean +/- SE maximal Vo2, determined on the cycle ergometer, was 42.2 +/- 2.3 at sea level and 35.6 +/- 1.7 ml.kg-1 .min-1 at altitude. There were no significant differences in daily Vo2 at any specific exercise intensity on days 1, 5, and 9 of exposure, nor were there any differences in endurance times at the two most difficult exercise intensities. Endurance times for 15- and 30-kg loads at 16% grade were 7.3 and 4.2 min, respectively. Measured energy expenditure was compared with that predicted by the formula of Pandolf et al. (J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 43: 577–581, 1977) and found to be significantly different. The differences could be attributed to measurements at metabolic rates exceeding 730 W or 2.1 1.min-1 Vo2. These data indicate that the prediction equation can be used at altitude for exercise intensities not exceeding this upper limit. The observed deviations from predicted values at the high exercise intensities could possibly be attributed to the occurrence of appreciable oxygen deficits and the inability to achieve steady-state conditions.

scholarly journals Low intrinsic running capacity is associated with reduced skeletal muscle substrate oxidation and lower mitochondrial content in white skeletal muscle

2011 ◽  
Vol 300 (4) ◽  
pp. R835-R843 ◽  
Author(s):  
Donato A. Rivas ◽  
Sarah J. Lessard ◽  
Misato Saito ◽  
Anna M. Friedhuber ◽  
Lauren G. Koch ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Insulin Sensitivity ◽  
Aerobic Capacity ◽  
Artificial Selection ◽  
White Muscle ◽  
Metabolic Diseases ◽  
Metabolic Health ◽  
Mitochondrial Content ◽  
Red Muscle ◽  
Selection For

Chronic metabolic diseases develop from the complex interaction of environmental and genetic factors, although the extent to which each contributes to these disorders is unknown. Here, we test the hypothesis that artificial selection for low intrinsic aerobic running capacity is associated with reduced skeletal muscle metabolism and impaired metabolic health. Rat models for low- (LCR) and high- (HCR) intrinsic running capacity were derived from genetically heterogeneous N:NIH stock for 20 generations. Artificial selection produced a 530% difference in running capacity between LCR/HCR, which was associated with significant functional differences in glucose and lipid handling by skeletal muscle, as assessed by hindlimb perfusion. LCR had reduced rates of skeletal muscle glucose uptake (∼30%; P = 0.04), glucose oxidation (∼50%; P = 0.04), and lipid oxidation (∼40%; P = 0.02). Artificial selection for low aerobic capacity was also linked with reduced molecular signaling, decreased muscle glycogen, and triglyceride storage, and a lower mitochondrial content in skeletal muscle, with the most profound changes to these parameters evident in white rather than red muscle. We show that a low intrinsic aerobic running capacity confers reduced insulin sensitivity in skeletal muscle and is associated with impaired markers of metabolic health compared with high intrinsic running capacity. Furthermore, selection for high running capacity, in the absence of exercise training, endows increased skeletal muscle insulin sensitivity and oxidative capacity in specifically white muscle rather than red muscle. These data provide evidence that differences in white muscle may have a role in the divergent aerobic capacity observed in this generation of LCR/HCR.

scholarly journals Artificial Selection for High Aerobic Capacity is Protective against Weight Gain via Thermogenesis?

2012 ◽  
Vol 26 (S1) ◽  
Author(s):  
Sira Maria Torvinen ◽  
Mika Silvennoinen ◽  
Maria Mikkonen ◽  
Lauren G. Koch ◽  
Steven L. Britton ◽  
...  
Keyword(s):  
Weight Gain ◽  
Aerobic Capacity ◽  
Artificial Selection ◽  
Selection For

Determination of Particulate Matter and Alkaloids (as Nicotine) in Cigarette Smoke

1964 ◽  
Vol 47 (2) ◽  
pp. 356-362
Author(s):  
C L Ogg
Keyword(s):  
Particulate Matter ◽  
Weight Gain ◽  
Cigarette Smoke ◽  
Analytical Methods ◽  
Filter Holder ◽  
Nicotine Delivery ◽  
Coefficients Of Variation ◽  
Selection For

Abstract A collaborative smoking study for the determination of particulate matter and nicotine deliveries of cigarettes, by a method chosen by the Analytical Methods Committee of the Tobacco Chemists’ Conference, was completed during the year. The 12 collaborators obtained coefficients of variation within laboratories of 4% and between laboratories of 10%. Each collaborator was asked to smoke 40 cigarettes (8 samples of 5 cigarettes). Non-filter (85 mm) cigarettes and filter (85 mm) cigarettes were analyzed. The cigarettes were conditioned for 24 hours at 75°F and 60% r.h. prior to selection for smoking. Cigarettes weighing within 20 mg of the average cigarette weight (50 randomly selected cigarettes) were marked to a 30 mm butt length. The cigarettes were smoked into a Cambridge filter holder by an automatic smoking machine which drew a 35 ml puff of 2-second duration once every minute. Five weight-selected cigarettes, marked to 30 mm butt, were smoked per Cambridge filter and the particulate matter (wet) was determined as the weight gain of the Cambridge filter. Nicotine delivery was determined by distilling the Cambridge filter pads and measuring the nicotine spectrophotometrically.

scholarly journals Daily Crude Oil Price Forecasting Based on Improved CEEMDAN, SCA, and RVFL: A Case Study in WTI Oil Market

Energies ◽  
2020 ◽  
Vol 13 (7) ◽  
pp. 1852 ◽  
Author(s):  
Jiang Wu ◽  
Feng Miu ◽  
Taiyong Li
Keyword(s):  
Crude Oil ◽  
Critical Role ◽  
Oil Prices ◽  
Ensemble Empirical Mode Decomposition ◽  
Functional Link ◽  
Intrinsic Factors ◽  
Crude Oil Prices ◽  
Target Values ◽  
Predicted Values

Crude oil is one of the strategic energies and plays an increasingly critical role effecting on the world economic development. The fluctuations of crude oil prices are caused by various extrinsic and intrinsic factors and usually demonstrate complex characteristics. Therefore, it is a great challenge for accurately forecasting crude oil prices. In this study, a self-optimizing ensemble learning model incorporating the improved complete ensemble empirical mode decomposition with adaptive noise (ICEEMDAN), sine cosine algorithm (SCA), and random vector functional link (RVFL) neural network, namely ICEEMDAN-SCA-RVFL, is proposed to forecast crude oil prices. Firstly, we employ ICEEMDAN to decompose the raw series of crude oil prices into a group of relatively simple subseries. Secondly, RVFL is used to forecast the target values for each decomposed subseries individually. Due to the complex parameter settings of ICEEMDAN and RVFL, SCA is introduced to optimize the parameters for ICEEMDAN and RVFL in the above decomposition and prediction stages simultaneously. Finally, we assemble the predicted values of all individual subseries as the final predicted values of crude oil prices. Our proposed ICEEMDAN-SCA-RVFL significantly outperforms the single and ensemble benchmark models, as demonstrated by a case study conducted using the time series of West Texas Intermediate (WTI) daily crude oil spot prices.

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