You are looking at 1-20 of 100 entries  for:

  • All : basic rest-activity cycle x
  • Science and technology x
clear all

View:

Overview

basic rest-activity cycle

A biological rhythm of waxing and waning alertness with a period of approximately 90 minutes in humans. During sleep it controls the cycles of REM and slow-wave sleep. Also called the ...

basic rest–activity cycle

basic rest–activity cycle n.   Quick reference

A Dictionary of Psychology (4 ed.)

Reference type:
Subject Reference
Current Version:
2015

... restactivity cycle n. A biological rhythm of waxing and waning alertness with a period of approximately 90 minutes in humans. During sleep it controls the cycles of REM and slow-wave sleep . Also called the restactivity cycle . BRAC ...

basic rest-activity cycle

basic rest-activity cycle  

A biological rhythm of waxing and waning alertness with a period of approximately 90 minutes in humans. During sleep it controls the cycles of REM and slow-wave sleep. Also called the rest-activity ...
chronobiology

chronobiology n.   Quick reference

A Dictionary of Psychology (4 ed.)

Reference type:
Subject Reference
Current Version:
2015

... n. The branch of biology concerned with biological rhythms . See biological clock , biological rhythm . See also alpha wave , basic restactivity cycle , beta wave , circadian rhythm , circannual rhythm , delta wave , gamma wave , infradian rhythm , menstrual cycle , sensorimotor rhythm , sleep–wake cycle , suprachiasmatic nucleus , telomere , theta wave , ultradian rhythm , Zeitgeber . [From Greek chronos time + English biology...

biological rhythm

biological rhythm n.   Quick reference

A Dictionary of Psychology (4 ed.)

Reference type:
Subject Reference
Current Version:
2015

...rhythm n. Any periodic, more-or-less regular fluctuation or cycle in a biological system or process that is not wholly under the control of environmental cues but is controlled centrally by a biological clock . It may be an ultradian rhythm such as a circannual rhythm or a menstrual cycle ; a circadian rhythm such as the sleep–wake cycle ; or an infradian rhythm such as an alpha wave , basic restactivity cycle , beta wave , delta wave , gamma wave , sensorimotor rhythm , or theta wave . See also chronobiology , pacemaker...

infradian rhythm

infradian rhythm n.   Quick reference

A Dictionary of Psychology (4 ed.)

Reference type:
Subject Reference
Current Version:
2015

...rhythm n . Any biological rhythm with a period of less than a day. See alpha wave , basic restactivity cycle , beta wave , delta wave , gamma wave , sensorimotor rhythm , theta wave . See also biological clock , chronobiology , Zeitgeber . Compare circadian rhythm , circannual rhythm , ultradian rhythm . [From Latin infra under + dies a...

sleep

sleep n.   Quick reference

A Dictionary of Psychology (4 ed.)

Reference type:
Subject Reference
Current Version:
2015

...III, and IV NREM sleep respectively. See also basal forebrain , basic restactivity cycle , circadian rhythm , delta sleep-inducing peptide , delta wave , dream ( 1 ) , dyssomnias , hypnagogic image , hypnopompic image , K complex , locus coeruleus , magnocellular nucleus , melatonin , nucleus gigantocellularis , paradoxical sleep , parasomnias , PGO spike , pineal gland , polysomnography , pseudoinsomnia , REM atonia , REM rebound , sleep spindle , sleep–wake cycle , sleepwalking , slow-wave sleep , subcoerulear nucleus...

Bacteria and Archaea

Bacteria and Archaea   Reference library

Encyclopedia of Evolution

Reference type:
Subject Reference
Current Version:
2005
Subject:
Science and technology, Life Sciences, Social sciences, Anthropology
Length:
3,133 words
Illustration(s):
2

...number of microbes deriving their existence from coupling the oxidation-reduction reactions is incredibly important for the cycling of elements on earth. Global cycles, including those of carbon, nitrogen, and sulfur, are driven primarily by the metabolic activity of microbes, and it is these activities that support plant and animal life on the planet. Most of what we know about microbes and their contribution to global cycles is derived from studies of microbes that have been isolated from all other organisms and grown in “pure cultures.” Growing a...

Nuclear Industry

Nuclear Industry   Reference library

Encyclopedia of Global Change

Reference type:
Subject Reference
Current Version:
2005
Subject:
Science and technology, Environmental Science, Social sciences, Environment
Length:
5,102 words
Illustration(s):
1

...linear energy transfer radiation. Gamma rays (γ) are photons emitted from the nucleus of a radionuclide during radioactive decay. source : From Mounfield ( 1991 , p. 333). High-volume, low-activity solid wastes arise in mining and uranium ore processing at the front end of the fuel cycle, from reactor operations, and from plant decommissioning. Generally speaking, low-activity wastes contain radionuclides with short half-lives and are short-lived. Most of the world's annual total of mined uranium—around 34,000 metric tons in 1995 —is mined in Canada (32...

Population Growth and the Environment

Population Growth and the Environment   Reference library

Encyclopedia of Climate and Weather (2 ed.)

Reference type:
Subject Reference
Current Version:
2011
Subject:
Science and technology, Earth Sciences and Geography, Social sciences, Environment
Length:
2,227 words
Illustration(s):
1

...emissions of other greenhouse gases result from activities related to population size (such as agriculture, the source of a large fraction of methane and nitrous oxide emissions), population growth may exert a major influence on the buildup of greenhouse gases. Another measure of the impact of the global population on the environment is the fraction of the terrestrial net primary productivity (NPP, the basic energy supply of all terrestrial animals) directly consumed, co-opted, or eliminated by human activity. This figure is now an estimated 40 percent. Of...

Biological Productivity

Biological Productivity   Reference library

Encyclopedia of Global Change

Reference type:
Subject Reference
Current Version:
2005

...dioxide in the atmosphere is fairly well mixed and its concentration generally varies by less than 5 percent seasonally and latitudinally. [See Carbon Cycle ; and Nitrogen Cycle .] Atmospheric carbon dioxide concentration has varied dramatically over geologic time, and has increased by more than 30 percent since the beginning of the Industrial Revolution, apparently as a result of human activities, including combustion of fossil fuels, forest clearing, and agriculture. This increase in global atmospheric carbon dioxide may have increased global primary...

Energy and Human Activity

Energy and Human Activity   Reference library

Encyclopedia of Global Change

Reference type:
Subject Reference
Current Version:
2005
Subject:
Science and technology, Environmental Science, Social sciences, Environment
Length:
8,105 words
Illustration(s):
7

...and materials are used—often by using improved design tools to minimize materials in basic designs and to ensure that production processes operate continuously at peak performance points. Changes in the mix of industries—away from traditional materials industries—have reduced the energy intensity of industry by 10–20 percent over the past two decades. The exception is Denmark, which appears to have shifted to more energy-intensive industries. Energy and Human Activity. Figure 4. U.S. Energy Use in Manufacturing. (Energy use data from U.S. Office of...

Amazonia, Deforestation Of

Amazonia, Deforestation Of   Reference library

Encyclopedia of Global Change

Reference type:
Subject Reference
Current Version:
2005
Subject:
Science and technology, Environmental Science, Social sciences, Environment
Length:
5,326 words
Illustration(s):
2

...carbon; this is the “medium” value from Nordhaus, 1991.) [See Ecotaxation .] Loss of water cycling Water cycling is different from biodiversity and carbon loss in that impacts of deforestation in this area fall directly on Brazil rather than being spread over the Earth as a whole. [See Hydrologic Cycle .] Several independent lines of evidence indicate that about half of the rainfall in the Brazilian Amazon is water that is recycled through the forest, the rest originating from water vapor blown into the region directly from the Atlantic Ocean (Gash et...

Amazonia and Deforestation

Amazonia and Deforestation   Reference library

The Oxford Companion to Global Change

Reference type:
Subject Reference
Current Version:
2009
Subject:
Science and technology, Environmental Science, Social sciences, Environment
Length:
5,747 words
Illustration(s):
2

...the purchase price of land today. These calculations use U.S.$7.3/ton C as the value of permanently sequestered carbon. Loss of water cycling Water cycling is different from biodiversity and carbon in that impacts of deforestation in this area fall directly on Brazil rather than being spread over the world as a whole. About 20–30% of the rainfall in the Brazilian Amazon is water that is recycled through the forest, the rest originating from water vapor blown into the region directly from the Atlantic Ocean ( Lean et al., 1996 ). Of the water entering the...

Carbon Dioxide

Carbon Dioxide   Reference library

Encyclopedia of Global Change

Reference type:
Subject Reference
Current Version:
2005
Subject:
Science and technology, Environmental Science, Social sciences, Environment
Length:
4,785 words
Illustration(s):
3

...Dioxide . Climate Change 19 (1991), 99–118. Moore B., III , and B. H. Braswell, Jr. Planetary Metabolism: Understanding the Carbon Cycle . Ambio 23 (February 1994), 4–12. CO 2 and the terrestrial biosphere Green, N. P. O. , G. W. Stout , and D. J. Taylor . Biological Science , vol. 1, Organisms, Energy and Environment. 2d ed. Cambridge: Cambridge University Press, 1990. Biology textbook that contains basic details of the biochemistry of photosynthesis. Leemans, R. Impacts of Greenhouse Gases and Climatic Change. In The Global Environment:...

Plate Tectonics

Plate Tectonics   Reference library

Encyclopedia of Global Change

Reference type:
Subject Reference
Current Version:
2005
Subject:
Science and technology, Environmental Science, Social sciences, Environment
Length:
6,065 words
Illustration(s):
5

...greenhouse mechanisms, of variable volatile production associated with plate tectonic volcanic activity at the ridge crests has scarcely been explored, but profound changes in climate could be effected. See also Earth Structure and Development ; Land Surface Processes ; and Natural Hazards . Arthur, M. A. , et al. Variations in the Global Carbon Cycle during the Cretaceous Related to Climate, Volcanism, and Changes in Atmospheric Carbon Dioxide. In The Carbon Cycle and Atmospheric Carbon Dioxide: Natural Variations Archean to Present , edited by E. T....

Plants

Plants   Reference library

Encyclopedia of Evolution

Reference type:
Subject Reference
Current Version:
2005
Subject:
Science and technology, Life Sciences, Social sciences, Anthropology
Length:
4,987 words
Illustration(s):
4

...plant morphology; excellent on life cycles. Graham, L. E. Origin of Land Plants . New York, 1993. A synthetic treatment of charophytes and the origin of land plants. Heywood V. H. , ed. Flowering Plants of the World . New York, 1978. A thoroughly illustrated compendium of information on angiosperm diversity. Judd, W. S. , C. S. Campbell , E. A. Kellogg , and P. F. Stevens . Plant Systematics. A Phylogenetic Approach . Sunderland, Mass., 1999. A phylogenetically oriented systematics textbook emphasizing basic principles and an overview of angiosperm...

Mobile Earth

Mobile Earth   Reference library

The Oxford Companion to Global Change

Reference type:
Subject Reference
Current Version:
2009

...or subduction volcanism. The effect on climate (through greenhouse mechanisms) of variable volatile production associated with plate-tectonic volcanic activity at the ridge crests has scarcely been explored, but it may be profound. Bibliography Arthur , M. A. , et al. “Variations in the Global Carbon Cycle During the Cretaceous Related to Climate, Volcanism, and Changes in Atmospheric CO 2 .” In The Carbon Cycle and Atmospheric CO 2 : Natural Variations, Archean to Present, edited by E. T. Sundquist and W. S. Broecker . Washington, D.C.: American Geophysical...

Water Quality

Water Quality   Reference library

Encyclopedia of Global Change

Reference type:
Subject Reference
Current Version:
2005
Subject:
Science and technology, Environmental Science, Social sciences, Environment
Length:
9,089 words
Illustration(s):
5

...monitoring activities can be found in Chapman ( 1996 ) and Adriansee et al. ( 1995 ). All monitoring activities should include at least the following steps: definition of objectives; monitoring design; field sampling and observations, including necessary hydrological measurements (e.g., water discharge, water table level); laboratory analyses, including data quality control, data storage, treatment, and reporting; and water quality assessment with respect to water use criteria, background references, and aquatic biota conservation. After one cycle of...

Disease

Disease   Reference library

Encyclopedia of Global Change

Reference type:
Subject Reference
Current Version:
2005
Subject:
Science and technology, Environmental Science, Social sciences, Environment
Length:
7,137 words
Illustration(s):
1

...to the human host by a mosquito and inoculated through the skin. Some pathogens have complicated cycles that involve one or more intermediate hosts, typically animals that support one stage of development of the pathogen. Other microbes, such as hantaviruses, reside in an animal, known as a reservoir host . Humans can become infected if they enter the habitat of the animal or if they come into contact with them or their secretions/excretions through other activities. The human may be irrelevant to the maintenance of the microbe in nature, although the human, if...

Disease

Disease   Reference library

The Oxford Companion to Global Change

Reference type:
Subject Reference
Current Version:
2009
Subject:
Science and technology, Environmental Science, Social sciences, Environment
Length:
7,032 words
Illustration(s):
1

...to the human host by a mosquito and inoculated through the skin. Some pathogens have complicated cycles that involve one or more intermediate hosts, typically animals that support one stage of development of the pathogen. Other microbes, such as hantaviruses, reside in an animal, known as a reservoir host. Humans can become infected if they enter the habitat of the animal or if they come into contact with them or their secretions/excretions through other activities. The human may be irrelevant to the maintenance of the microbe in nature, although the human, if...

View: