scholarly journals A NEW COORDINATE FOR PELAGIC AVIAN NAVIGATION

2021 ◽  
Author(s):  
David Morley
Keyword(s):  
Experimental Evidence ◽  
Direct Experimental Evidence ◽  
Avian Navigation ◽  
The Moment

A new, previously uninvestigated, candidate for a navigational coordinate is put forward. If accepted this would make the process by which ocean birds navigate understandable. There is no direct experimental evidence to support this at the moment, but "Theory guides but experiments decide"

scholarly journals Constancy of the optimum temperature of an enzyme under varying concentrations of substrate and of enzyme

1914 ◽  
Vol 88 (602) ◽  
pp. 258-262
Keyword(s):  
Experimental Evidence ◽  
Aspergillus Oryzae ◽  
Hydrolytic Enzyme ◽  
Fixed Duration ◽  
Optimum Temperature ◽  
Enzymic Hydrolysis ◽  
Main Interest ◽  
General Law ◽  
The Moment ◽  
Hydrolysis Of

In a recent paper a new enzymic relation is recorded. For the enzymic hydrolysis of salicin—by the enzyme which Gabriel Bertrand and the author have named salicinase —it is found that, in an action of fixed duration, the temperature of greatest activity of the ferment is always the same, whatever the dilutions of substrate and of enzyme adopted for the determination. In other words, the duration of the action being constant, the optimum tem­perature of the ferment is independent of the concentration both of the substrate and of the enzyme. The observation is suggestive: if true of one enzyme it may be true of all, and possibly becomes the enunciation of a general law. Herein, for the moment, lies its main interest. In the present paper further experimental evidence for this hypothesis in given, in the case of another hydrolytic enzyme, the maltase of Aspergillus oryzæ (taka-diastase).

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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