Oxygen and the upper limits to animal design and performance.

1998 ◽  
Vol 201 (8) ◽  
pp. 1065-1072 ◽  
Author(s):  
R K Suarez
Keyword(s):  
Energy Metabolism ◽  
Surface Area ◽  
Body Mass ◽  
Current Evidence ◽  
Tracheal System ◽  
Flying Insects ◽  
Upper Limit ◽  
O2 Transport ◽  
Upper Limits ◽  
Functional Capacities

Mass-specific rates of aerobic metabolism VO2/Mb) scale in inverse proportion to body mass (Mb). Thus, small hummingbirds display the highest VO2/Mb known among vertebrates. Among all animals, higher VO2/Mb values are known only in flying insects. The high body-mass-specific rates of metabolism seen in hummingbirds are made possible by high lung O2 diffusing capacities, cardiac outputs, ratios of capillary surface area to muscle fiber surface area, mitochondrial volume densities, cristae surface densities and concentrations of enzymes involved in energy metabolism. Current evidence from control analyses of O2 transport through the respiratory and cardiovascular systems and of metabolic fluxes through pathways of energy metabolism indicates shared control of maximum flux rates among multiple steps (i.e. the absence of single rate-limiting steps). This supports the suggestion that functional capacities at each step in linear pathways or processes are matched to each other, and provides an explanation for why the up-regulation of functional capacities has occurred at virtually all steps in the evolution of the smallest vertebrate homeotherms. Flying insects make use of a tracheal system for O2 transport and, like hummingbirds, possess a highly up-regulated biochemical machinery for substrate oxidation. Studies of hummingbirds and honeybees reveal closer matches between biochemical flux capacities and maximum physiological flux rates than in animals capable of lower maximum VO2/Mb. It is proposed that the upper limits to functional capacities set the upper limit to VO2/Mb. This upper limit to aerobic metabolic rate may contribute, along with other factors, towards establishing the lower limit to vertebrate homeotherm size.

A simple relationship to calculate eel surface area

2004 ◽  
Vol 54 (2) ◽  
pp. 131-136 ◽  
Author(s):  
Marc Belhomme ◽  
Aurelie Vettier ◽  
Philippe Sébert
Keyword(s):  
Energy Metabolism ◽  
Linear Relationship ◽  
Surface Area ◽  
Body Mass ◽  
Body Length ◽  
Body Surface ◽  
Simple Formula ◽  
Simple Relationship

AbstractEnergy metabolism has a linear relationship with body surface (BS). However, this surface area cannot be easily measured. Consequently, a simple formula including body mass (BM) and body length (BL) is proposed for the eel. The formula BS = BL0.53 × BM 0.49 × 3.983 gives BS calculated values which show very low variations compared to the measured values (0.16 ± 1.07%). The formula may be employed in the study of eel energetics and various aspects of applied aquaculture.

Vitamin-A-Exzess durch Pferdefleischprodukte mit hohen Leberanteilen

2013 ◽  
Vol 41 (01) ◽  
pp. 31-36
Author(s):  
E. Kienzle ◽  
N. Becker
Keyword(s):  
Vitamin A ◽  
Eine Analyse ◽  
Upper Limit ◽  
Upper Limits

ZusammenfassungIm Rahmen einer Eliminationsdiät wird regelmäßig Pferdefleisch eingesetzt. Aus Gründen der Praktikabilität verwenden Tierbesitzer häufig kommerziell erhältliches Pferdefleisch aus der Dose. Aufgrund eines Berichts von Zervikalspondylosen bei einer auf Futtermittel allergischen Katze erfolgte eine Analyse verschiedener auf Pferdefleisch basierender Produkte hinsichtlich des Vitamin-AGehalts.In 14 Pferdefleischerzeugnissen wurde der Vitamin-A-Gehalt (Retinol) analysiert. Der Gehalt an umsetzbarer Energie wurde mithilfe von Schätzformeln auf Basis der Deklaration berechnet.In Produkten mit deklarierten Anteilen von Leber, Innereien oder tierischen Nebenprodukten konnten zum Teil erhebliche Vitamin-A-Gehalte festgestellt werden. Bei alleiniger Verfütterung eines dieser Produkte (Deckung des durchschnittlichen Energiebedarfs) würde die Vitamin-A-Versorgung nur knapp unter dem Safe Upper Limit der Katze sowie oberhalb des Safe Upper Limits beim Hund liegen.Bei All-Meat-Produkten sollte nicht nur die Deklaration, sondern auch der Inhalt näher betrachtet werden, um einen Hinweis auf eventuell hohe Leberanteile zu erhalten.Aufgrund der Ergebnisse ist eine exzessive Vitamin-A-Aufnahme bei langfristiger Verfütterung von Pferdefleischprodukten mit hohen Leberanteilen nicht auszuschließen.

scholarly journals Search for π0 decays to invisible particles

2021 ◽  
Vol 2021 (2) ◽  
Author(s):  
E. Cortina Gil ◽  
◽  
A. Kleimenova ◽  
E. Minucci ◽  
S. Padolski ◽  
...  
Keyword(s):  
Higgs Boson ◽  
Standard Model ◽  
Confidence Level ◽  
Branching Ratio ◽  
Standard Model Higgs Boson ◽  
Scalar Mixing ◽  
Upper Limit ◽  
Upper Limits ◽  
The Standard Model ◽  
Model Independent

Abstract The NA62 experiment at the CERN SPS reports a study of a sample of 4 × 109 tagged π0 mesons from K+ → π+π0(γ), searching for the decay of the π0 to invisible particles. No signal is observed in excess of the expected background fluctuations. An upper limit of 4.4 × 10−9 is set on the branching ratio at 90% confidence level, improving on previous results by a factor of 60. This result can also be interpreted as a model- independent upper limit on the branching ratio for the decay K+ → π+X, where X is a particle escaping detection with mass in the range 0.110–0.155 GeV/c2 and rest lifetime greater than 100 ps. Model-dependent upper limits are obtained assuming X to be an axion-like particle with dominant fermion couplings or a dark scalar mixing with the Standard Model Higgs boson.

scholarly journals Effects of Triphala on Lipid and Glucose Profiles and Anthropometric Parameters: A Systematic Review

2021 ◽  
Vol 26 ◽  
pp. 2515690X2110110
Author(s):  
Wiraphol Phimarn ◽  
Bunleu Sungthong ◽  
Hiroyuki Itabe
Keyword(s):  
Body Mass Index ◽  
Body Weight ◽  
Blood Glucose ◽  
Waist Circumference ◽  
Lipid Profile ◽  
Body Mass ◽  
The Body ◽  
Current Evidence ◽  
Diabetic Patients ◽  
Anthropometric Parameters

Aim. The efficacy of triphala on lipid profile, blood glucose and anthropometric parameters and its safety were assessed. Methods. Databases such as PubMed, ScienceDirect, Web of Science, and Thai Library Integrated System (ThaiLIS) were systematically searched to review current evidence of randomized controlled trials (RCT) on triphala. RCTs investigating the safety and efficacy of triphala on lipid profile, blood glucose and anthropometric parameters were included. Study selection, data extraction, and quality assessment were performed independently by 2 authors. Results. Twelve studies on a total of 749 patients were included. The triphala-treated groups showed significantly reduced low-density lipoprotein-cholesterol, total cholesterol and triglyceride in 6 studies. Five RCTs demonstrated triphala-treated groups led to statistically significant decrease in body weight, body mass index and waist circumference of obese patients. Moreover, triphala significantly decreased fasting blood glucose level in diabetic patients but not in people without diabetes. No serious adverse event associated with triphala was reported during treatment. Conclusions. This review summarized a current evidence to show triphala might improve the lipid profile, blood glucose, the body weight, body mass index and waist circumference under certain conditions. However, large well-designed RCTs are required to confirm this conclusion.

Relationships among Cutaneous Surface Area, Cutaneous Mass, and Body Mass in Frogs: A Reappraisal

1992 ◽  
Vol 65 (6) ◽  
pp. 1135-1147 ◽  
Author(s):  
Colleen R. Talbot ◽  
Martin E. Feder
Keyword(s):  
Surface Area ◽  
Body Mass

scholarly journals Upper limits on the extent of seafloor anoxia during the PETM from uranium isotopes

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Matthew O. Clarkson ◽  
Timothy M. Lenton ◽  
Morten B. Andersen ◽  
Marie-Laure Bagard ◽  
Alexander J. Dickson ◽  
...  
Keyword(s):  
Carbon Cycle ◽  
Global Scale ◽  
Uranium Isotopes ◽  
Biogeochemical Model ◽  
Emission Scenarios ◽  
Isotope Data ◽  
Upper Limit ◽  
Thermal Maximum ◽  
Upper Limits ◽  
Anoxic Events

AbstractThe Paleocene Eocene Thermal Maximum (PETM) represents a major carbon cycle and climate perturbation that was associated with ocean de-oxygenation, in a qualitatively similar manner to the more extensive Mesozoic Oceanic Anoxic Events. Although indicators of ocean de-oxygenation are common for the PETM, and linked to biotic turnover, the global extent and temporal progression of de-oxygenation is poorly constrained. Here we present carbonate associated uranium isotope data for the PETM. A lack of resolvable perturbation to the U-cycle during the event suggests a limited expansion of seafloor anoxia on a global scale. We use this result, in conjunction with a biogeochemical model, to set an upper limit on the extent of global seafloor de-oxygenation. The model suggests that the new U isotope data, whilst also being consistent with plausible carbon emission scenarios and observations of carbon cycle recovery, permit a maximum ~10-fold expansion of anoxia, covering <2% of seafloor area.

scholarly journals Limited Access to Food and Physiological Trade‐Offs in a Long‐Distance Migrant Shorebird. I. Energy Metabolism, Behavior, and Body‐Mass Regulation

2009 ◽  
Vol 82 (5) ◽  
pp. 549-560 ◽  
Author(s):  
François Vézina ◽  
Magali Petit ◽  
Deborah M. Buehler ◽  
Anne Dekinga ◽  
Theunis Piersma
Keyword(s):  
Energy Metabolism ◽  
Body Mass ◽  
Long Distance ◽  
Limited Access ◽  
Body Mass Regulation ◽  
Trade Offs ◽  
Access To Food

scholarly journals Reactive quenching of electronically excited NO<sub>2</sub><sup>∗</sup> and NO<sub>3</sub><sup>∗</sup> by H<sub>2</sub>O as potential sources of atmospheric HO<sub><i>x</i></sub> radicals

2018 ◽  
Vol 18 (19) ◽  
pp. 14005-14015 ◽  
Author(s):  
Terry J. Dillon ◽  
John N. Crowley
Keyword(s):  
Gas Phase ◽  
Laser Excitation ◽  
Pulsed Laser ◽  
Work Rate ◽  
Rate Coefficients ◽  
Phase Reaction ◽  
Gas Phase Reaction ◽  
Upper Limit ◽  
Upper Limits ◽  
Electronically Excited

Abstract. Pulsed laser excitation of NO2 (532–647 nm) or NO3 (623–662 nm) in the presence of H2O was used to initiate the gas-phase reaction NO2∗+H2O → products (Reaction R5) and NO3∗+H2O → products (Reaction R12). No evidence for OH production in Reactions (R5) or (R12) was observed and upper limits for OH production of k5b/k5<1×10-5 and k12b/k12<0.03 were assigned. The upper limit for k5b∕k5 renders this reaction insignificant as a source of OH in the atmosphere and extends the studies (Crowley and Carl, 1997; Carr et al., 2009; Amedro et al., 2011) which demonstrate that the previously reported large OH yield by Li et al. (2008) was erroneous. The upper limit obtained for k12b∕k12 indicates that non-reactive energy transfer is the dominant mechanism for Reaction (R12), though generation of small but significant amounts of atmospheric HOx and HONO cannot be ruled out. In the course of this work, rate coefficients for overall removal of NO3∗ by N2 (Reaction R10) and by H2O (Reaction R12) were determined: k10=(2.1±0.1)×10-11 cm3 molecule−1 s−1 and k12=(1.6±0.3)×10-10 cm3 molecule−1 s−1. Our value of k12 is more than a factor of 4 smaller than the single previously reported value.

scholarly journals Erythrocyte Volume, Plasma Volume, and Lean Body Mass in Adult Men and Women

Blood ◽  
1969 ◽  
Vol 33 (5) ◽  
pp. 649-667 ◽  
Author(s):  
JOHN A. RETZLAFF ◽  
W. NEWLON TAUXE ◽  
JOSEPH M. KIELY ◽  
CHARLES F. STROEBEL
Keyword(s):  
Surface Area ◽  
Lean Body Mass ◽  
Body Mass ◽  
Plasma Volume ◽  
Normal Subjects ◽  
Skinfold Thickness ◽  
Regression Equations ◽  
Surface Area Ratio ◽  
Erythrocyte Volume ◽  
Normal Males

Abstract Erythrocyte volume, plasma volume, hematocrit, lean body mass (from total body water), skinfold thickness (at three sites), arm circumference, height, and weight were measured in 40 normal males, 38 normal females, and 12 obese females. From these data on the normal subjects, equations for estimating erythrocyte and plasma volumes were derived. Equations utilizing combined height-weight, surface area, height-weight-skinfold thickness, or lean body mass were found to be the most accurate for predicting erythrocyte and plasma volumes in normal and in obese subjects. The body:venous hematocrit ratio (BH:VH) and the variability of this ratio in our subjects were determined and discussed. Errors in indirect estimates of blood volumes based on this ratio are presented. Erythrocyte and plasma volume standards based on height-weight regression equations or surface area ratio equation are suggested for use in clinical laboratories. Tables and a nomogram based on these equations have been prepared and are available on request.

Body Mass Index and Body Surface Area and Their Associations with Outcomes in Stage II and III Colon Cancer

2012 ◽  
Vol 44 (2) ◽  
pp. 203-210 ◽  
Author(s):  
Sina Alipour ◽  
Hagen F. Kennecke ◽  
Ryan Woods ◽  
Howard J. Lim ◽  
Caroline Speers ◽  
...  
Keyword(s):  
Body Mass Index ◽  
Colon Cancer ◽  
Surface Area ◽  
Body Surface Area ◽  
Body Mass ◽  
Body Surface ◽  
Stage Ii
Sign in / Sign up

Export Citation Format

Share Document