Energetic consequences of metabolic depression in tropical and temperate-zone lizards

1999 ◽  
Vol 47 (2) ◽  
pp. 133 ◽  
Author(s):  
Keith A. Christian ◽  
Gavin S. Bedford ◽  
Timothy J. Schultz
Keyword(s):  
Energy Savings ◽  
Environmental Parameters ◽  
Thermal Acclimation ◽  
Temperate Zone ◽  
Energy Budgets ◽  
Tropical Species ◽  
Metabolic Depression ◽  
Laboratory Studies ◽  
Conservation Of Energy ◽  
Dry Tropics

One response of ectothermic animals to periods of inactivity is inverse acclimation, or metabolic depression, which results in the conservation of energy. Most studies of metabolic depression and acclimation have involved temperate-zone species, and the information from tropical species has been largely restricted to laboratory studies that failed to demonstrate thermal acclimation of metabolism. Recently, metabolic depression has been shown in several species of reptiles from the wet-dry tropics of northern Australia during the dry season. We review existing data on the energy budgets of temperate and tropical species during periods of inactivity and make calculations of energy saved due to metabolic depression across a range of temperatures. Because tropical species experience relatively high temperatures during periods of inactivity, they have a greater potential for energy savings, any enhancement of their metabolic depression is disproportionately advantageous with respect to energy savings, and in some species metabolic depression is probably essential for survival. Thus, we would expect metabolic depression to be well developed in some tropical reptiles. The lack of thermal acclimation in laboratory studies indicates that environmental parameters other than temperature (such as food or water) may initiate metabolic depression in tropical species. Higher temperatures, however, magnify the energy savings accomplished by metabolic depression.

scholarly journals A Mass and Energy Conservation Analysis of Drift in the CMIP6 Ensemble

2021 ◽  
Author(s):  
Damien Irving
Keyword(s):  
Climate Models ◽  
Heat Content ◽  
Moisture Flux ◽  
Cmip5 Models ◽  
Energy Budgets ◽  
Freshwater Flux ◽  
Atmospheric Moisture ◽  
State Variables ◽  
Conservation Of Energy ◽  
Ocean Mass

Coupled climate models are prone to ‘drift’ (long-term unforced trends in state variables) due to incomplete spin-up and non-closure of the global mass and energy budgets. Here we assess model drift and the associated conservation of energy, mass and salt in CMIP6 and CMIP5 models. For most models, drift in globally-integrated ocean mass and heat content represents a small but non-negligible fraction of recent historical trends, while drift in atmospheric water vapor is negligible. Model drift tends to be much larger in time-integrated ocean heat and freshwater flux, net top-of-the-atmosphere radiation (netTOA) and moisture flux into the atmosphere (evaporation minus precipitation), indicating a substantial leakage of mass and energy in the simulated climate system. Most models are able to achieve approximate energy budget closure after drift is removed, but ocean mass budget closure eludes a number of models even after de-drifting and none achieve closure of the atmospheric moisture budget. The magnitude of the drift in the CMIP6 ensemble represents an improvement over CMIP5 in some cases (salinity and time-integrated netTOA) but is worse (time-integrated ocean freshwater and atmospheric moisture fluxes) or little changed (ocean heat content, ocean mass and time-integrated ocean heat flux) for others, while closure of the ocean mass and energy budgets after drift removal has improved.

scholarly journals An Ontology-Based Framework for Building Energy Management with IoT

Electronics ◽  
2019 ◽  
Vol 8 (5) ◽  
pp. 485 ◽  
Author(s):  
Clement Lork ◽  
Vishal Choudhary ◽  
Naveed Ul Hassan ◽  
Wayes Tushar ◽  
Chau Yuen ◽  
...  
Keyword(s):  
Energy Consumption ◽  
Energy Management ◽  
Management System ◽  
Energy Savings ◽  
Environmental Parameters ◽  
Building Energy ◽  
Building Energy Efficiency ◽  
Commercial Building ◽  
Building Energy Management ◽  
Building Management

In this paper, we develop an ontology-based framework for energy management in buildings. We divide the functional architecture of a building energy management system into three interconnected modules that include building management system (BMS), benchmarking (BMK), and evaluation & control (ENC) modules. The BMS module is responsible for measuring several useful environmental parameters, as well as real-time energy consumption of the building. The BMK module provides the necessary information required to understand the context and cause of building energy efficiency or inefficiency, and also the information which can further differentiate normal and abnormal energy consumption in different scenarios. The ENC module evaluates all the information coming from BMS and BMK modules, the information is contextualized, and finally the cause of energy inefficiency/abnormality and mitigating control actions are determined. Methodology to design appropriate ontology and inference rules for various modules is also discussed. With the help of actual data obtained from three different rooms in a commercial building in Singapore, a case study is developed to demonstrate the application and advantages of the proposed framework. By mitigating the appropriate cause of abnormal inefficiency, we can achieve 5.7%, 11.8% and 8.7% energy savings in Room 1, Room 2, and Room 3 respectively, while creating minimum inconvenience for the users.

Energetics: the costs of living and reproducing for an individual cephalopod

1996 ◽  
Vol 351 (1343) ◽  
pp. 1083-1104 ◽  
Keyword(s):  
Specific Dynamic Action ◽  
Energy Budgets ◽  
Food Conversion ◽  
Laboratory Studies ◽  
Feeding Rates ◽  
Historical Factors ◽  
In The Wild ◽  
Excretion Rates ◽  
The Cost ◽  
Conversion Efficiencies

Cephalopods, like all other animals, have to decide how to allocate resources; maintenance processes, growth of somatic and reproductive tissues, and locomotor activity all have costs. We should like to be able to identify these costs and discover how efficiently cephalopods make use of the prey that they capture and digest. Cephalopods generally grow fast and mature rapidly; a first task is to determine how accurately laboratory studies reflect growth in the wild, because much of the information we need (such as food conversion efficiencies, excretion rates or the costs of locomotion) can be collected only from animals kept in the laboratory. Comparison of laboratory feeding and growth rates for octopods, sepioids and teuthoids with fisheries data suggests that data collected from cephalopods fed ad libitum in the laboratory may be used validly to construct energy budgets representative of individuals in the wild. The immediate cost of feeding (the specific dynamic action) has been thoroughly documented in Octopus , as has the longer-term elevation or depression of metabolic rate by feeding or starvation; it is assumed that similar costs will be found in squid. The cost of locomotion has been studied in both octopods and squid, but we have only limited data on how much time the animals spend moving, and how rapidly, in the wild. Excretory and faecal losses are assessed from laboratory studies, and maintenance costs estimated from feeding rates that just maintain body mass in the laboratory. Comparison of gross and net food conversion efficiencies suggest that squid convert food into tissues less efficiently than octopods, owing primarily to their greater time spent in locomotion. We present a representative series of energy budgets for octopods (based on Octopus ) and squids (based on Illex and Loligo ), for starving, feeding, migrating and maturing individuals. A major contrast is provided by Nautilus, which lives for ten or twenty years and grows only slowly. Finally we speculate on the possible biochemical and historical factors that may have limited the adaptive radiation of cephalopods, resulting in a group lacking herbivores, detritivores or filter-feeders but extremely successful as carnivores.

scholarly journals Torpor duration, more than temperature, is key to hummingbird nighttime energy savings

2018 ◽  
Author(s):  
A Shankar ◽  
RJ Schroeder ◽  
SM Wethington ◽  
CH Graham ◽  
DR Powers
Keyword(s):  
Energy Management ◽  
Energy Savings ◽  
Natural Habitat ◽  
Natural Environments ◽  
List Type ◽  
Laboratory Studies ◽  
Ambient Temperatures ◽  
Torpor Bout ◽  
Bout Duration ◽  
Temperature Regimes

ABSTRACTTorpor is an important energy saving strategy in small endotherms, but it has been insufficiently studied in natural field conditions. Building on what we know from laboratory studies, we compared torpor use across hummingbird species and different natural temperature regimes to explore predominant hypotheses about torpor use and evaluate the possible effects of environmental variation on energy management.We found that the probability of an individual entering torpor was correlated with mass and unrelated to nighttime temperature, and that hummingbirds at both warm tropical and cooler temperate sites used torpor.Energy savings in torpor were maximized as ambient temperatures approached a species’ minimum body temperature consistent with laboratory studies; energy savings ranged between 65-92% of energy per hour in torpor compared to normothermy.However, variation in total nighttime energy expenditure was more significantly influenced by torpor bout duration than by the variation in energy savings in torpor.Our results show that a small endotherm’s nighttime energy management in its natural habitat is more affected by torpor bout duration, which is linked to photoperiod, than by temperature. This result suggests that in their natural environments, hummingbirds are able to save energy in torpor across a range nighttime temperature, indicating that they may have sufficient physiological flexibility to tolerate climatic variation.

scholarly journals Energy Audit and Analysis of an Institutional Building under Subtropical Climate

2018 ◽  
Vol 8 (2) ◽  
pp. 845 ◽  
Author(s):  
Yazed Yasin Ghadi ◽  
Ali M. Baniyounes
Keyword(s):  
Energy Consumption ◽  
Energy Savings ◽  
Environmental Parameters ◽  
Subtropical Climate ◽  
University Campus ◽  
Energy Usage ◽  
Climate Conditions ◽  
Heating And Cooling ◽  
And Performance ◽  
Heating And Cooling Load

<p>Evaluation and estimation of energy consumption are essential in order to classify the amount of energy used and the way it is utilized in building. Hence, the possibility of any energy savings potential and energy savings opportunities can be identified. The intention of this article is to study and evaluate energy usage pattern of the Central Queensland University campus’ buildings, Queensland, Australia. This article presents the field survey results from the audit of an office building and performance-related measurements of the indoor environmental parameters, for instance, indoor air temperature, humidity and energy consumption concerned to the indoor heating and cooling load. Monthly observed energy usage information was employed to investigate influence of the climate conditions on energy usage.</p>

scholarly journals Effect of supply air temperature on conservation of energy in air conditioning of space

2011 ◽  
pp. 51-54
Author(s):  
V. N. Bartari ◽  
S. P. S. Rajput
Keyword(s):  
Air Temperature ◽  
Distribution System ◽  
Energy Savings ◽  
Thermal Environment ◽  
Temperature Sensors ◽  
Air Distribution ◽  
Conservation Of Energy ◽  
Buoyancy Flow ◽  
Flow Energy ◽  
The Impact

In HVAC applications, huge amount of energy is utilized in fans and blowers to maintain the flow. In this paper energy savings associated with air distribution is discussed. In a most commonly used air distribution system, uniform thermal environment in the occupied space is established. An alternative to this method is the under floor air distribution system (UFAD) which is in its fantasy state. Thermal stratification can be established in this method due to the buoyancy flow of the air. In this paper assessment of the impact of temperature sensors in energy savings is done in UFAD system. It is observed that by the placement of temperature sensors in the occupied space, supply air temperature can be controlled while maintaining the comfort conditions. By optimal conditions of the temperature and volume flow, energy savings can be achieved due to reduction in energy requirements in refrigeration and ventilation. The comfort criteria of ASHRAE standard 55-92 is taken.

scholarly journals Testosterone Does not Increase in Response to Conspecific Challenges in the White-Bellied Antbird (Myrmeciza Longipes), A Resident Tropical Passerine

The Auk ◽  
2006 ◽  
Vol 123 (1) ◽  
pp. 61-66
Author(s):  
Bradley C. Fedy ◽  
Bridget J. M. Stutchbury
Keyword(s):  
Breeding Season ◽  
Temperate Zone ◽  
Plasma Testosterone ◽  
Tropical Species ◽  
Zone Model ◽  
Territorial Aggression ◽  
Social Instability ◽  
Testosterone Levels ◽  
Testosterone Secretion ◽  
Removal Experiments

Abstract Resident tropical passerines that exhibit year-round territorial aggression do not fit well into the temperate-zone model, because testosterone does not increase substantially during the breeding season. We studied patterns of testosterone secretion in the White-bellied Antbird (Myrmeciza longipes), a resident tropical species in Panama that maintains territories year-round and is capable of aggression throughout the year, regardless of its stage of reproduction. Levels of plasma testosterone were low (mean = 0.30 ng mL−1) throughout the breeding and nonbreeding seasons and did not differ between them. Testosterone also did not increase in response to simulated conspecific intrusions. When we used temporary removal experiments to induce natural, extended conflict between males, testosterone levels did not increase in response to the extended social instability that resulted. White-bellied Antbirds demonstrate an apparent uncoupling of testosterone and territorial aggression throughout the year. La Testosterona no Aumenta como Respuesta a Desafíos de Individuos Coespecíficos en Myrmeciza longipes, un Paserino Residente de la Zona Tropical

scholarly journals A Wireless Gas Sensor Network to Monitor Indoor Environmental Quality in Schools

Sensors ◽  
2018 ◽  
Vol 18 (12) ◽  
pp. 4345 ◽  
Author(s):  
Alvaro Ortiz Perez ◽  
Benedikt Bierer ◽  
Louisa Scholz ◽  
Jürgen Wöllenstein ◽  
Stefan Palzer
Keyword(s):  
Sensor Network ◽  
Gas Sensor ◽  
Environmental Quality ◽  
Energy Savings ◽  
Environmental Parameters ◽  
Well Being ◽  
Sensor Nodes ◽  
Indoor Environmental Quality ◽  
Monitoring And Control ◽  
And Control

Schools are amongst the most densely occupied indoor areas and at the same time children and young adults are the most vulnerable group with respect to adverse health effects as a result of poor environmental conditions. Health, performance and well-being of pupils crucially depend on indoor environmental quality (IEQ) of which air quality and thermal comfort are central pillars. This makes the monitoring and control of environmental parameters in classes important. At the same time most school buildings do neither feature automated, intelligent heating, ventilation, and air conditioning (HVAC) systems nor suitable IEQ monitoring systems. In this contribution, we therefore investigate the capabilities of a novel wireless gas sensor network to determine carbon dioxide concentrations, along with temperature and humidity. The use of a photoacoustic detector enables the construction of long-term stable, miniaturized, LED-based non-dispersive infrared absorption spectrometers without the use of a reference channel. The data of the sensor nodes is transmitted via a Z-Wave protocol to a central gateway, which in turn sends the data to a web-based platform for online analysis. The results show that it is difficult to maintain adequate IEQ levels in class rooms even when ventilating frequently and that individual monitoring and control of rooms is necessary to combine energy savings and good IEQ.

scholarly journals Seasonal Variation of Soil Respiration in the Mongolian Oak (Quercus mongolica Fisch. Ex Ledeb.) Forests at the Cool Temperate Zone in Korea

Forests ◽  
2020 ◽  
Vol 11 (9) ◽  
pp. 984
Author(s):  
Gyung Soon Kim ◽  
Seung Jin Joo ◽  
Chang Seok Lee
Keyword(s):  
Soil Respiration ◽  
Environmental Parameters ◽  
Field Measurements ◽  
Temperate Zone ◽  
Short Time Scale ◽  
Strongly Correlated ◽  
Quercus Mongolica ◽  
Cool Temperate ◽  
Mongolian Oak ◽  
Short Time

To investigate the variation in seasonal soil respiration (SR) as a function of soil temperature (Ts) and soil water content (SWC) in Mongolian oak (Quercus mongolica) forests in urban (Mt. Nam) and well-reserved (Mt. Jeombong) areas in South Korea, we conducted continuous field measurements of SR and other environmental parameters (Ts and SWC) using an automated chamber system. Overall, the SR rates in both stands were strongly correlated with the Ts variable during all seasons. However, abrupt fluctuations in SR were significantly related to episodic increases in SWC on a short time scale during the growing season. The integrated optimal regression models for SR using Ts at a depth of 5 cm and SWC at a depth of 15 cm yielded the following: the SR rate in Mt. Nam = SR(Ts) + ΔSR(Ts) = 104.87 exp(0.1108Ts) − 10.09(SWC)2 + 604.2(SWC) − 8627.7 for Ts ≥ 0 °C, and the SR rate in Mt. Jeombong = SR(Ts) + ΔSR(Ts) = 95.608 exp(0.1304Ts) − 33.086(SWC)2 + 1949.2(SWC) − 28499 for Ts ≥ 0 °C. In both cases, SR = 0 for Ts < 0 °C. As per these equations, the estimated annual total SRs were 1339.4 g C m−2 for Mt. Nam and 1003.0 g C m−2 for Mt. Jeombong. These values were quite similar to the measured values in field. Our results demonstrate that the improved empirical equation is an effective tool for estimating and predicting SR variability and provide evidence that the SR of Q. mongolica forests in the cool temperate zone of Korean Peninsula depends on Ts and SWC variables.

Design and Simulation of Automatic Room Temperature by Using Fuzzy Control

2017 ◽  
Vol 4 (1) ◽  
pp. 67-78
Author(s):  
Maung Kyaw Soe Moe
Keyword(s):  
Fuzzy Logic ◽  
Air Conditioning ◽  
Fuzzy Logic Controller ◽  
Energy Savings ◽  
Air Conditioning System ◽  
Efficient Operation ◽  
Conservation Of Energy ◽  
Conditioning Equipment ◽  
Comfort Parameters ◽  
Thesis Work

In air conditioning system, efficient operation of air conditioning equipment to suit the user demand is important and to achieve that, Fuzzy Logic controller can play a key role in formulating the next generation of control technology for the traditional air conditioning equipment. The target of this research is to develop a fuzzy logic control which will allow less usage of energy by optimum operation of air conditioning which would also promote Conservation of Energy. The control system in this study also would need to achieve a Stable Climate Condition in the room within the limits of control set points and promote convenient to the users by automatic control. The control strategy proposed in this thesis work is fuzzy logic controller (FLC). A MATLAB fuzzy program tool is used to develop a fuzzy logic controller to achieve within the comfort parameters of temperature and artificial lighting as well as energy savings. Simulink program in MATLAB will also be used to simulate the fuzzy logic in this Thesis work. Based on the findings observed on the case study described in this Thesis Report, the savings achieved by the Fuzzy Logic Air Conditioning System is about 66%.With these results, it can be concluded that the objective of this Thesis work has been full filled)

Sign in / Sign up

Export Citation Format

Share Document