Molecular Actions

Wind speed has velocity components in all directions so that there are vertical motions as well as horizontal ones. These random motions of widely different scales and periods are essentially responsible for the movement and diffusion of pollutants about the mean downwind path. These motions can be considered atmospheric turbulence. If the scale of a turbulent motion (i.e., the size of an eddy) is larger than the size of the pollutant plume in its vicinity, the eddy will move that portion of the plume. If an eddy is smaller than the plume, its effect will be to difhise or spread out the plume. This diffusion caused by eddy motion is widely variable in the atmosphere, blit even when the effect of this diffusion is least, it is in the vicinity of three orders of magnitude greater than diffusion by molecular action alone. 

MolekuLar-grSsse,/. molecular magnitude mo> lecular weight, -kraft, /. molecular force, -reibung, /, molecular friction, -stoning, /. molecular disturbance, -strahl, m. moleculat ray. -verbindung, /, molecular compoimd. -warme, /, molecular heat, -wirkung, /. molecular action (or effect), -zustand, m. molecular state or condition, molecularity. 

Retinoids. Figure 1 Intracellular pathways and molecular action of retinoids. 

Olsnes, S., and Pihl, A. (1982c) Toxic lectins and related proteins. In Molecular Action of Toxins and Viruses (P. Cohen, and S. van Heynigen, eds.), p. 51. Elsevier, New York. 

The behavioural effects of two antidepressants with opposite molecular actions, ie. tianeptine (a serotonin reuptake enhancer) and fluoxetine (a serotonin reuptake blocker) have been assessed and it was concluded that, apart from the effects on serotonin reuptake, these dmgs have other mechanisms playing an important role in the anti-depressant action <00AF5>. 

R. L Blakley, Molecular Actions and Targets for Cancer Therapeutic Agents A. C. 

Granting Laplace s fundamental assumption, we see that the molecules in the interior of a liquid are subject to attraction in all directions, but that a different condition prevails in a layer at the surface, the thickness of which is smaller than the radius of molecular action. In this layer the molecules are subject to unbalanced attraction from the adjoining molecules in the interior, in other words, to an inward pull, which keeps the surface in a state of tension. If we imagine a small prominence raised somewhere in the surface, the tendency of this inward pull would be to bring it into the general... 

Hombach-Klonisch, S., Pocar, P., Kietz, S. and Klonisch, T. (2005) Molecular actions of polyhalogenated arylhydrocarbons (PAHs) in... 

Snyder SH, Sklar P. (1984). Behavioral and molecular actions of caffeine focus on adenosine. J Psychiatr Res. 18(2) 91-106. 

Thomas, S.R., and Stocker, R., 2000, Molecular action of vitamin E in lipoprotein oxidation impheations for atherosclerosis. Free Radio. Biol. Med. 28 1795-1805. 

Chan, E.S., and Cronstein, B.N. (2002) Molecular action of methotrexate in inflammatory diseases. Arthritis Research. 4, 266-273. 

Durham PL, Russo AF New insights into the molecular actions of serotonergic antimigraine drugs. Pharmacol Ther 2002 94 77. [PMID 12191595]... 

The mechanism of action of the vitamin D metabolites remains under active investigation. However, calcitriol is well established as the most potent agent with respect to stimulation of intestinal calcium and phosphate transport and bone resorption. Calcitriol appears to act on the intestine both by induction of new protein synthesis (eg, calcium-binding protein and TRPV6, an intestinal calcium channel) and by modulation of calcium flux across the brush border and basolateral membranes by a means that does not require new protein synthesis. The molecular action of calcitriol on bone has received less attention. However, like PTH, calcitriol can induce RANK ligand in osteoblasts and proteins such as osteocalcin, which may regulate the mineralization process. The metabolites 25(OH)D and 24,25(OH)2D are far less... 

Regardless of what other conservation equations may be appropriate, a bulk-fluid mass-conservation equation is invariably required in any fluid-flow situation. When N is the mass m, the associated intensive variable (extensive variable per unit mass) is r) = 1. That is, r) is the mass per unit mass is unity. For the circumstances considered here, there is no mass created or destroyed within a control volume. Chemical reaction, for example, may produce or consume individual species, but overall no mass is created or destroyed. Furthermore the only way that net mass can be transported across the control surfaces is by convection. While individual species may diffuse across the control surfaces by molecular actions, there can be no net transport by such processes. This fact will be developed in much depth in subsequent sections where mass transport is discussed. 

In the present state of science, it seems hardly possible to frame a dynamic theory of molecular action which shall embrace the phenomena of thermodynamics, of radiation, and of the electrical manifestations which accompany the union of atoms. .. Even if we confine our attention to phenomena distinctively thermodynamic, we do not escape difficulties in as simple a matter as the number of degrees of freedom of a diatomic gas. .. Certainly, one is building on an insecure foundation, who rests his work on hypotheses concerning the constitution of matter. 

It may also be mentioned here that in specific molecular actions a particularly marked influence of like molecules upon one another is often to be observed. This is encountered in various ways in spectroscopy, in the extinction of the polarization of mercury resonance radiation with increasing vapour pressure, in the damping of fluorescence in concentrated solutions, and in various chemical reactions. As an example of the latter the decomposition of acetaldehyde (p. 70) may be quoted, where collisions between two molecules of the aldehyde are much more effective than collisions of aldehyde molecules with those of other gases. 

Differences in physical, chemical and stereochemical properties can be manifested in different bioactivities, if these parameters influence absorption, distribution, mechanism of the molecular action, biotransformation reaction and excretion. 

Molecular Action changing temperature of thermistors creating images on photographic film. 

Sembdner, G. Parthier, B. (1993). The biochemistry and the physiological and molecular actions of jasmonates. Ann. Rev. Plant Physiol. Plant Mol. Biol. 44, 569-589. 

Shiba Y, Kinoshita T, Chuman H, Taketani Y, Takeda E, Kato Y, Naito M, Kawabata K, Ishisaka A, Terao J, Kawai Y. 2008. Flavonoids as substrates and inhibitors of myeloperoxidase Molecular actions of aglycone and the metabolites. Chem Res Toxicol. 21 16-1609. 

Maneuf YP, Gonzalez MI, Sutton KS, et al. Cellular and molecular action of the putative GABA-mimetic, gabapentin. Cell Mol Life Sci. 2003 60 742-750. 

Kirken RA, Wang YL. Molecular actions of sirolimus sirolimus and rnTbr. Transplant Proc. 2003 35(suppl) 227S-230S. 

Kaplan, M., Hayek, T., Raz, A., Coleman, R., Domfeld, L., Vaya, J., and Aviram, M., Biochemical and molecular action of nutrients pomegranate juice supplementation to atherosclerotic mice reduces macrophage lipid peroxidation, cellular cholesterol accumulation and development of atherosclerosis, J. Nutr., 131, 2082-2089, 2001. 

Wyatt G. R. and Davey K. G. (1996) Cellular and molecular actions of juvenile hormone. II. Roles of juvenile hormone in adult insects. Adv. Insect Physiol. 26, 1-155. 

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