Energy-budget strategies for growth in mammals and birds

1984 ◽  
Vol 38 (2) ◽  
pp. 147-155 ◽  
Author(s):  
J. K. Kirkwood ◽  
A. J. F. Webster
Keyword(s):  
Energy Budget ◽  
Rapid Growth ◽  
Energy Exchange ◽  
Maturation Time ◽  
Maturation Rate ◽  
Energy Exchanges ◽  
Altricial Birds ◽  
Precocial Birds ◽  
Time And Energy ◽  
Mature Size

ABSTRACTThe concepts of metabolic time and size are used, respectively, to compare maturing time and energy exchanges during growth in homeotherms. Maturation rate, expressed per unit of mature size (A1/4) is relatively constant for mammals, irrespective of attempts by man to select for rapid growth. Precocial birds mature more rapidly, however, and altricial birds more rapidly still. These differences are explained in terms of different patterns of energy exchange. It is proposed that maturation time is ultimately determined by size-related constraints on rate of metabolism during growth.

A note on growth rates and maturation rates in beef bulls

1982 ◽  
Vol 35 (2) ◽  
pp. 281-284 ◽  
Author(s):  
A. J. F. Webster ◽  
A. A. M. Ahmed ◽  
J. P. Frappell
Keyword(s):  
Growth Rate ◽  
Growth Curve ◽  
Growth Rates ◽  
Rapid Growth ◽  
Mean Value ◽  
Rapid Growth Rate ◽  
Maturation Rate ◽  
Metabolic Age ◽  
Beef Bulls ◽  
Mature Size

ABSTRACTValues for weight and age of beef bulls at stud have been used to describe growth beyond the point of inflexion of the growth curve. Using the concept of ‘metabolic age’ it was shown that the maturation rate in Aberdeen Angus and Friesian bulls was close to a reported interspecies mean value. Hereford and Charolais bulls both matured relatively rapidly. Variation between individuals within a breed was consistent with the hypothesis that it is possible to select for rapid growth rate without necessarily selecting for an increase in mature size.

scholarly journals Energy exchange analysis in droplet dynamics via the Navier–Stokes–Cahn–Hilliard model

2016 ◽  
Vol 797 ◽  
pp. 389-430 ◽  
Author(s):  
L. F. R. Espath ◽  
A. F. Sarmiento ◽  
P. Vignal ◽  
B. O. N. Varga ◽  
A. M. A. Cortes ◽  
...  
Keyword(s):  
Energy Budget ◽  
Energy Exchange ◽  
Navier Stokes ◽  
Energy Budgets ◽  
Liquid Droplets ◽  
Droplet Dynamics ◽  
Flow Features ◽  
Budget Equation ◽  
Energy Exchanges ◽  
Insight Into

We develop the energy budget equation of the coupled Navier–Stokes–Cahn–Hilliard (NSCH) system. We use the NSCH equations to model the dynamics of liquid droplets in a liquid continuum. Buoyancy effects are accounted for through the Boussinesq assumption. We physically interpret each quantity involved in the energy exchange to gain further insight into the model. Highly resolved simulations involving density-driven flows and the merging of droplets allow us to analyse these energy budgets. In particular, we focus on the energy exchanges when droplets merge, and describe flow features relevant to this phenomenon. By comparing our numerical simulations to analytical predictions and experimental results available in the literature, we conclude that modelling droplet dynamics within the framework of NSCH equations is a sensible approach worthy of further research.

Founding a Field Theory of Work

2014 ◽  
pp. 34-64
Author(s):  
Raymon R. Bruce
Keyword(s):  
Field Theory ◽  
Organization Development ◽  
Textile Industry ◽  
Energy Exchange ◽  
Stakeholder Management ◽  
Work Organization ◽  
Wicked Problem ◽  
Organization Model ◽  
Energy Exchanges ◽  
Issue Analysis

This chapter traces the origin of the concept of work in five staged sections. The first section examines the question, what is work? Work originally referred to “doing,” that is, work organization, synergy, and energy. The second section develops the Greek word family for work into a dynamic model of doing. The third section shows how nature guides working change through energy exchange. It examines how a work as re-organization model would function in nature's jurisdictional domain of guiding energy exchanges. Nature's laws provide guidance for self-governing latitude to energy jurisdictional domains' evolutionary change. The fourth section examines policymaking as human guidance imitating nature. Policymaking limits individual self-governance to guide a specified social community of people (polis) doing work. Policymaking is explored to see how humans use policymaking to govern themselves and their cultural social groups including governments by using nature's use of laws as guidance. Policymaking is also a form of laying down basic parameters of work as re-organization through energy exchanges in the ambient environment. Policies are human artifacts designed help a social group work well together. Part five presents an issue analysis as an invited Organization Development consultant to help find ways for the Sri Lankan government, the University of Moratuwa, and the apparel and textile industry to work together in their extreme makeover of human resource development of their apparel and textile industry. Action training and research, stakeholder management, and wicked problem issue analysis are the organization development methods used to demonstrate this field theory of work re-organization through energy exchange.

scholarly journals Do small precocial birds enter torpor to conserve energy during development?

2020 ◽  
Vol 223 (21) ◽  
pp. jeb231761
Author(s):  
Yaara Aharon-Rotman ◽  
Gerhard Körtner ◽  
Chris B. Wacker ◽  
Fritz Geiser
Keyword(s):  
Body Temperature ◽  
Metabolic Rate ◽  
Surface Temperature ◽  
Heat Loss ◽  
Body Mass ◽  
Infrared Thermometer ◽  
Common Strategy ◽  
Energy Conserving ◽  
Altricial Birds ◽  
Precocial Birds

ABSTRACTPrecocial birds hatch feathered and mobile, but when they become fully endothermic soon after hatching, their heat loss is high and they may become energy depleted. These chicks could benefit from using energy-conserving torpor, which is characterised by controlled reductions of metabolism and body temperature (Tb). We investigated at what age the precocial king quail Coturnix chinensis can defend a high Tb under a mild thermal challenge and whether they can express torpor soon after achieving endothermy to overcome energetic and thermal challenges. Measurements of surface temperature (Ts) using an infrared thermometer showed that king quail chicks are partially endothermic at 2–10 days, but can defend high Tb at a body mass of ∼13 g. Two chicks expressed shallow nocturnal torpor at 14 and 17 days for 4–5 h with a reduction of metabolism by >40% and another approached the torpor threshold. Although chicks were able to rewarm endogenously from the first torpor bout, metabolism and Ts decreased again by the end of the night, but they rewarmed passively when removed from the chamber. The total metabolic rate increased with body mass. All chicks measured showed a greater reduction of nocturnal metabolism than previously reported in quails. Our data show that shallow torpor can be expressed during the early postnatal phase of quails, when thermoregulatory efficiency is still developing, but heat loss is high. We suggest that torpor may be a common strategy for overcoming challenging conditions during development in small precocial and not only altricial birds.

Inelastic Scattering and Interference

1997 ◽  
Vol 3 (S2) ◽  
pp. 1033-1034
Author(s):  
D. Van Dyck
Keyword(s):  
Electron Diffraction ◽  
Energy Loss ◽  
Inelastic Scattering ◽  
Energy Exchange ◽  
Position Vector ◽  
Inelastic Electron ◽  
Global System ◽  
Interference Fringes ◽  
Energy Exchanges ◽  
Generating System

Recently it has been a matter of controversy whether inelastically scattered electrons can yield interference fringes so as to obtain holograms, and in particular whether compensation of energy loss in the object by energy gain in the source will maintain coherence [1]. In discussions about coherence (and wave mechanisms in general) it is always dangerous to rely on intuitive arguments (exchange of energy, time of interaction, etc.). In this work we will start from the most general approach, which is inspired by the treatment of inelastic electron diffraction crystals by Yoshioka in 1957 [2]. Energy exchanges are always described quantummechanically by an Hamiltonian. Therefore we can only investigate the balance between energy exchange properly if electron, object, and source are described by one global Hamiltonian. With source we mean the whole electron generating system (emitter, accelerator, condensor).Consider a global system consisting of an electron, with position vector r, an object with particle vectors ri, and a source with particles at rα.

Increase of Parental Effort with Brood Size in a Nidifugous Bird

The Auk ◽  
1987 ◽  
Vol 104 (4) ◽  
pp. 688-693 ◽  
Author(s):  
Martin Schindler ◽  
Jürg Lamprecht
Keyword(s):  
Parental Care ◽  
Brood Size ◽  
Detailed Examination ◽  
Feeding Time ◽  
Parental Effort ◽  
Males And Females ◽  
Altricial Birds ◽  
Precocial Birds ◽  
Positive Correlations ◽  
Anser Indicus

Abstract Positive correlations of brood size with some parental activities [vigilance (in females), approaching young (in males and females), and attack (in males)] and a negative correlation of female feeding time with brood size were found in a sample of 23 semicaptive Bar-headed Goose (Anser indicus) families. Detailed examination of these correlations suggests that some components of parental care in geese represent "shared parental investment" (Lazarus and Inglis 1978, 1986). The benefits of parental care are divided among the offspring, so that in precocial birds, as in altricial birds, clutch size may be adapted to selection pressures that act after the young hatch.

scholarly journals Energy Exchange and Localization in Essentially Nonlinear Oscillatory Systems: Canonical Formalism

2016 ◽  
Vol 84 (1) ◽  
Author(s):  
O. V. Gendelman ◽  
T. P. Sapsis
Keyword(s):  
Conservation Laws ◽  
Harmonic Balance ◽  
Energy Exchange ◽  
Canonical Formalism ◽  
Dynamical Models ◽  
Oscillatory Systems ◽  
Impact Oscillators ◽  
Energy Exchanges ◽  
The Subject ◽  
The Relationship

Over recent years, a lot of progress has been achieved in understanding of the relationship between localization and transport of energy in essentially nonlinear oscillatory systems. In this paper, we are going to demonstrate that the structure of the resonance manifold can be conveniently described in terms of canonical action–angle (AA) variables. Such formalism has important theoretical advantages: all resonance manifolds may be described at the same level of complexity, appearance of additional conservation laws on these manifolds is easily proven both in autonomous and nonautonomous settings. The harmonic balance-based complexification approach, used in many previous studies on the subject, is shown to be a particular case of the canonical formalism. Moreover, application of the canonic averaging allows treatment of much broader variety of dynamical models. As an example, energy exchanges in systems of coupled trigonometrical and vibro-impact oscillators are considered.

scholarly journals Energy Exchanges at Contact Events Guide Sensorimotor Integration Across Intermodal Delays

2017 ◽  
Author(s):  
Ali Farshchiansadegh ◽  
Alessandra Sciutti ◽  
Assaf Pressman ◽  
Ilana Nisky ◽  
Ferdinando A. Mussa-Ivaldi
Keyword(s):  
Energy Exchange ◽  
Prolonged Exposure ◽  
Sensory Information ◽  
Different Types ◽  
Energy Exchanges ◽  
Transient Events ◽  
The Difference ◽  
New Interpretation ◽  
Temporal Perturbation ◽  
The Brain

ABSTRACTOne must know the mass of an object to accurately predict how it moves under the effect of an applied force. Similarly, the brain must represent the arm’s inertia to predict the arm’s movements elicited by commands impressed upon the muscles. Here, we present evidence suggesting that the integration of sensory information leading to the representation of the arm’s inertia does not take place continuously in time but only at discrete transient events, in which kinetic energy is exchanged between the arm and the environment. We used a visuomotor delay to induce crossmodal variations in state feedback and uncovered that the difference between visual and proprioceptive velocity estimations at isolated collision events was compensated by a change in the representation of arm inertia. The compensation maintained an invariant estimate across modalities of the expected energy exchange with the environment. This invariance captures different types of dysmetria observed across individuals following prolonged exposure to a fixed intermodal temporal perturbation and provides a new interpretation for cerebellar ataxia.

Measuring model improvement using surface energy budget process relationships: the impact of a new snow model

2020 ◽  
Author(s):  
Jonathan Day ◽  
Gabriele Arduini ◽  
Linus Magnusson ◽  
Irina Sandu ◽  
Anton Beljaars ◽  
...  
Keyword(s):  
Surface Energy ◽  
Energy Budget ◽  
Energy Exchange ◽  
Weather Prediction ◽  
Surface Energy Budget ◽  
Diagnostic Tools ◽  
Holistic View ◽  
Skill Scores ◽  
Model Improvement ◽  
The Impact

<p>Energy exchange at the snow-atmosphere interface in winter governs the evolution of temperature at the surface and within the snow, preconditioning the snowpack for melt during spring. This study illustrates a set of diagnostic tools that are useful for evaluating the energy exchange at the Earth surface in a numerical weather prediction model from a process-based perspective using in-situ observations. In particular, a new way to measure model improvement using relationships between different terms in the surface energy budget (SEB) is presented. These process-oriented diagnostics provide a holistic view the realism of the balance of terms in the SEB, ensuring that improvements in headline skill scores, such as 2m temperature, are happening for the right reasons. Correctly capturing such process relationships is a necessary step to achieve reliable weather forecasts.</p><p>These diagnostic techniques are applied to assess the impact of a new multi-layer snow scheme in the ECMWF-Integrated Forecast System at two high-Arctic sites (Summit, Greenland and Sodankylä, Finland). The multi-layer scheme is expected to replace a single layer snow scheme enhancing the 2m temperature forecast accuracy and reliability across the northern hemisphere in boreal winter. </p>

Sign in / Sign up

Export Citation Format

Share Document