6,869 research outputs found
Hydrogen storage in the form of metal hydrides
Reversible reactions between hydrogen and such materials as iron/titanium and magnesium/ nickel alloy may provide a means for storing hydrogen fuel. A demonstration model of an iron/titanium hydride storage bed is described. Hydrogen from the hydride storage bed powers a converted gasoline electric generator
Critical behaviour of the compactified theory
We investigate the critical behaviour of the -component Euclidean model at leading order in -expansion. We consider it in
three situations: confined between two parallel planes a distance apart
from one another, confined to an infinitely long cylinder having a square
cross-section of area and to a cubic box of volume . Taking the mass
term in the form , we retrieve Ginzburg-Landau
models which are supposed to describe samples of a material undergoing a phase
transition, respectively in the form of a film, a wire and of a grain, whose
bulk transition temperature () is known. We obtain equations for the
critical temperature as functions of (film), (wire), (grain) and of
, and determine the limiting sizes sustaining the transition.Comment: 12 pages, no figure
Effect of pre-analytical treatments on bovine milk acute phase proteins
Background
Samples for diagnostic procedures often require some form of pre-analytical preparation for preservation or safe handling during transportation prior to analysis in the laboratory. This is particularly important for milk samples which frequently need preservatives to retain milk composition as close to that found in freshly collected samples as possible.
Methods
Milk samples were treated by heating at 56 °C for 30 min or preserved by addition of either potassium dichromate or bronopol respectively. Haptoglobin (Hp), mammary associated serum amyloid A3 (M-SAA3) and C-reactive protein (CRP) were measured in the various treatment groups and in control samples which were not treated, using enzyme linked immunoassays. The concentrations of each APP were compared between treated and non-treated groups using the Wilcoxon signed ranks tests.
Results
Heat treatment of samples was found to have a significant lowering effect on milk M-SAA3 and CRP but not Hp. The use of potassium dichromate and bronopol as preservatives in milk had no significant effects on milk Hp and M-SAA3 concentration but lowered milk CRP values compared to controls.
Conclusions
The observed effects of heating and preservative use on milk APP should be taken into consideration when assaying samples which have undergone heat treatment as a result of international transfer regulations involving biological samples or samples needing chemical preservation prior to transport to laboratory
Crescimento micelial e germinação de esporos de patógenos de trigo em meios de cultura mais fungicidas 'in vitro'.
Editores técnicos: Joseani Mesquita Antunes, Ana LÃdia Variani Bonato, Márcia Barrocas Moreira Pimentel
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