Results 251 to 260 of about 7,619,054 (294)

Energy of activation

Journal of Chemical Education, 1969
Spinning a half sphere until it comes to a rest on its flat side serves as an analogy to a system of molecules that must acquire a certain amount of energy until they become products.
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Physical activity and energy requirements

The American Journal of Clinical Nutrition, 1995
Differences in physical activity represent the largest source of variability in energy requirements, both within and between individuals. Chronic changes in physical activity can produce chronic changes in energy requirements that, if not compensated for, can lead to changes in the level at which body weight and body composition are maintained over ...
J O, Hill, C, Melby, S L, Johnson, J C, Peters   +3 more
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Activation energies of the ATPase activity of sarcoplasmic reticulum

Biochemical and Biophysical Research Communications, 1974
Summary Arrhenius plots of Ca ++ -stimulated ATP hydrolysis by sarcoplasmic reticulum (SR) show breaks (T t ) at 16.7°C and 11.5°C for rabbit and lobster preparations, respectively. The energies of activation (Eact) are about 10 and 19.5 Kcal/mole above and below T t , respectively, and are similar for both lobster and rabbit SR.
V M, Madeira, M C, Antunes-Madeira, A P, Carvalho   +2 more
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ERDA's fossil energy activities

Environmental Science & Technology, 1976
Highlights of the direction of ERDA's fossil fuel activities are reviewed. Synfuels from coal and enhanced methods to recover oil, natural gas and oil shale may be competitive and socially acceptable options to alternative energy sources in the not-too-distant future.
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Active inference and free energy

Behavioral and Brain Sciences, 2013
AbstractWhy do brains have so many connections? The principles exposed by Andy Clark provide answers to questions like this by appealing to the notion that brains distil causal regularities in the sensorium and embody them in models of their world. For example, connections embody the fact that causes have particular consequences.
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Energy Cost of Sexual Activity

Archives of Internal Medicine, 1970
To the Editor. —The article by Hellerstein and Friedman "Sexual Activity and the Postcoronary Patient" (Arch Intern Med 125: 987-999, 1970) deserves comment regarding the inferences about the energy cost of sexual activity. To assess the oxygen cost of sexual activity, the authors have used the heart rate during sexual intercourse and compared it with
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Medium reorganization energy and enzymatic reaction activation energy

Journal of Theoretical Biology, 1985
Reorganization and activation energies for charge transfer reactions occurring inside a dielectric sphere have been calculated by solving the problem of polar medium reorganization within and outside a dielectric sphere placed in another infinite dielectric. The dielectric sphere is assumed to simulate a protein globule, i.e. an enzyme molecule. It has
, Kharkats YuI, L I, Krishtalik
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Active Transport and Transfer of Energy

Nature, 1963
THE transport of ions and molecules across the cell membrane against a concentration gradient is usually defined by the term ‘active transport’. The word ‘active’ conveys the idea of active participation of the cells in these transport processes, the energy required being supplied by the metabolic processes within the cells.
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Energy coding and energy functions for local activities of the brain

Neurocomputing, 2009
In this paper, the intrinsic relationship between energy consumption and neural information coding in local neural networks of the cerebral cortex is studied. The energy functions of a variety of membrane potential are obtained under some conditions of mutual coupling at both the supra-threshold and the sub-threshold states in a neural population ...
Rubin Wang, Zhikang Zhang, Guanrong Chen
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Fuzzy Energy-Based Active Contours

IEEE Transactions on Image Processing, 2009
This paper presents a novel fast model for active contours to detect objects in an image, based on techniques of curve evolution. The proposed model can detect objects whose boundaries are not necessarily defined by gradient, based on the minimization of a fuzzy energy, which can be seen as a particular case of a minimal partition problem.
Stelios Krinidis, Vassilios Chatzis
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