scholarly journals Toroidal Dipolar Response in a Metamaterial

Science ◽  
2010 ◽  
Vol 330 (6010) ◽  
pp. 1510-1512 ◽  
Author(s):  
T. Kaelberer ◽  
V. A. Fedotov ◽  
N. Papasimakis ◽  
D. P. Tsai ◽  
N. I. Zheludev
Keyword(s):  
Experimental Evidence ◽  
Parity Violation ◽  
Particle Physics ◽  
Direct Evidence ◽  
Classical Electrodynamics ◽  
Electromagnetic Response ◽  
Direct Experimental Evidence ◽  
Electromagnetic Interactions ◽  
Naturally Occurring

Toroidal multipoles are fundamental electromagnetic excitations different from those associated with the familiar charge and magnetic multipoles. They have been held responsible for parity violation in nuclear and particle physics, but direct evidence of their existence in classical electrodynamics has remained elusive. We report on the observation of a resonant electromagnetic response in an artificially engineered medium, or metamaterial, that cannot be attributed to magnetic or charge multipoles and can only be explained by the existence of a toroidal dipole. Our direct experimental evidence of the toroidal response brings attention to the often ignored electromagnetic interactions involving toroidal multipoles, which could be present in naturally occurring systems, especially at the macromolecule level, where toroidal symmetry is ubiquitous.

scholarly journals Direct Evidence that the Poly(A) Tail of Influenza A Virus mRNA Is Synthesized by Reiterative Copying of a U Track in the Virion RNA Template

1999 ◽  
Vol 73 (4) ◽  
pp. 3473-3476 ◽  
Author(s):  
Leo L. M. Poon ◽  
David C. Pritlove ◽  
Ervin Fodor ◽  
George G. Brownlee
Keyword(s):  
Influenza Virus ◽  
Experimental Evidence ◽  
Influenza A Virus ◽  
Influenza A ◽  
Direct Evidence ◽  
Evidence Based ◽  
Direct Experimental Evidence ◽  
Plausible Hypothesis

ABSTRACT The poly(A) tail of influenza virus mRNA is thought to be synthesized by reiterative copying of the U track near the 5′ end of the virion RNA template. This has been widely accepted as a plausible hypothesis, but until now there has been no direct experimental evidence for it. Here, we report such direct evidence based on the fact that (i) replacing the U track with an A track directs synthesis of products with poly(U) tails, both in vitro and in vivo, and (ii) interrupting the U track abolishes polyadenylation in vitro.

Overexpression of cysteine dioxygenase reduces intracellular cysteine and glutathione pools in HepG2/C3A cells

2007 ◽  
Vol 293 (1) ◽  
pp. E62-E69 ◽  
Author(s):  
John E. Dominy ◽  
Jesse Hwang ◽  
Martha H. Stipanuk
Keyword(s):  
Steady State ◽  
Experimental Evidence ◽  
Cysteine Dioxygenase ◽  
Wild Type ◽  
Hepatic Expression ◽  
Direct Experimental Evidence ◽  
Homeostatic Response ◽  
Catabolic Enzyme ◽  
In Cells

Cysteine levels are carefully regulated in mammals to balance metabolic needs against the potential for cytotoxicity. It has been postulated that one of the major regulators of intracellular cysteine levels in mammals is cysteine dioxygenase (CDO). Hepatic expression of this catabolic enzyme increases dramatically in response to increased cysteine availability and may therefore be part of a homeostatic response to shunt excess toxic cysteine to more benign metabolites such as sulfate or taurine. Direct experimental evidence, however, is lacking to support the hypothesis that CDO is capable of altering steady-state intracellular cysteine levels. In this study, we expressed either the wild-type (WT) or a catalytically inactivated mutant (H86A) isoform of CDO in HepG2/C3A cells (which do not express endogenous CDO protein) and cultured them in different concentrations of extracellular cysteine. WT CDO, but not H86A CDO, was capable of reducing intracellular cysteine levels in cells incubated in physiologically relevant concentrations of cysteine. WT CDO also decreased the glutathione pool and potentiated the toxicity of CdCl2. These results demonstrate that CDO is capable of altering intracellular cysteine levels as well as glutathione levels.

Large magnetostriction and direct experimental evidence for anisotropy compensation in Tb0.4−xNdxDy0.6(Fe0.8Co0.2)1.93 Laves compounds

2014 ◽  
Vol 137 ◽  
pp. 274-276 ◽  
Author(s):  
J.J. Liu ◽  
Z.B. Pan ◽  
X.Y. Liu ◽  
Z.R. Zhang ◽  
X.H. Song ◽  
...  
Keyword(s):  
Experimental Evidence ◽  
Direct Experimental Evidence

scholarly journals THE COEXISTENCE OF PROTOZOAN-LIKE PARASITES AND MENINGOENCEPHALITIS IN MICE

1924 ◽  
Vol 40 (1) ◽  
pp. 51-62 ◽  
Author(s):  
E. V. Cowdry ◽  
F. M. Nicholson
Keyword(s):  
Experimental Evidence ◽  
Small Proportion ◽  
Clinical Symptoms ◽  
The Other ◽  
Laboratory Mice ◽  
Direct Experimental Evidence

A small proportion of laboratory mice, which appear to be normal, are in reality suffering from an obscure disease characterized by the presence of marked meningoencephalitic lesions which are often accompanied by protozoan-like parasites. Both the lesions and the parasites closely resemble others previously reported in rabbits, which likewise fail to reveal themselves by pronounced clinical symptoms. In the absence of direct experimental evidence it is suggested either that one species of parasite is capable of producing the lesions in both animals, or else that we have to do with two kinds of parasites which are closely related and, in the stages thus far observed, are indistinguishable one from the other.

Oxygenation and organic-matter preservation in marine sediments: Direct experimental evidence from ancient organic carbon–rich deposits

Geology ◽  
2005 ◽  
Vol 33 (11) ◽  
pp. 889 ◽  
Author(s):  
Leon Moodley ◽  
Jack J. Middelburg ◽  
Peter M.J. Herman ◽  
Karline Soetaert ◽  
Gert J. de Lange
Keyword(s):  
Organic Matter ◽  
Organic Carbon ◽  
Experimental Evidence ◽  
Marine Sediments ◽  
Direct Experimental Evidence
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