3,615 research outputs found
Efficacy of phenothiazine in the treatment of sheep for control of internal parasites
"February, 1946."Treating ewes once in December and once the following March with a full dose of liquid phenothiazine and every 28 days thereafter with 1 1/2 per cent copper sulphate until the following December did not control nodular worm infestation even though at the beginning of the experiment the sheep were placed upon clean pasture.Treating sheep with liquid phenothiazine every four weeks from December to March (giving a total of four treatments) and then giving them 1 1/2 per cent copper sulphate every 28 days did not
control nodular worm infestations. The 1 1/2 per cent copper sulphate solution was found very satisfactory in keeping the lambs free from Haemonchus contortus. Treating sheep with liquid phenothiazine every four weeks from December to early April and then allowing them access to pheno-thiazine-salt mixture (1 part phenothiazine to 10 parts salt) was very satisfactory in controlling nodular worm infestation. This method of handling sheep held the Haemonchus contortus infestation down to an average of about 19 per lamb. This same method of handling did not satisfactorily control ostertagia, nematodirus, cooperia or tapeworms. Whipworm counts were not materially different in any of the three experiments. Average weight of the lambs was very much higher in Experiment III when the sheep had access to phenothiazine and salt mixture than it was in Experiments I and II. Phenothiazine has not been found toxic to sheep either in a 1 to10 phenothiazine-salt mixture or when the medicine has been given as a drench every 28 days throughout the entire year. The use of phenothiazine has not interfered with breeding efficiency. Worm egg counts by the flotation method have not contributed any aid in this study, but would be useful in sheep infested with only one species of parasite or with species that can be definitely identified by microscopic examination alone
DDFT calibration and investigation of an anisotropic phase-field crystal model
The anisotropic phase-field crystal model recently proposed and used by
Prieler et al. [J. Phys.: Condens. Matter 21, 464110 (2009)] is derived from
microscopic density functional theory for anisotropic particles with fixed
orientation. Further its morphology diagram is explored. In particular we
investigated the influence of anisotropy and undercooling on the process of
nucleation and microstructure formation from atomic to the microscale. To that
end numerical simulations were performed varying those dimensionless parameters
which represent anisotropy and undercooling in our anisotropic phase-field
crystal (APFC) model. The results from these numerical simulations are
summarized in terms of a morphology diagram of the stable state phase. These
stable phases are also investigated with respect to their kinetics and
characteristic morphological features.Comment: It contain 13 pages and total of 7 figure
Social and clinical predictors of prostate cancer treatment decisions among men in South Carolina
OBJECTIVE:
To assess social and clinical influences of prostate cancer treatment decisions among white and black men in the Midlands of South Carolina. METHODS:
We linked data collected on treatment decision making in men diagnosed with prostate cancer from 1996 through 2002 with clinical and sociodemographic factors collected routinely by the South Carolina Central Cancer Registry (SCCCR). Unconditional logistic regression was used to assess social and clinical influences on treatment decision. RESULTS:
A total of 435 men were evaluated. Men of both races who chose surgery (versus radiation) were more likely to be influenced by their physician and by family/friends. Black men who chose surgery also were ~5 times more likely to make independent decisions (i.e., rather than be influenced by their doctor). White men who chose surgery were twice as likely to be influenced by the desire for cure and less likely to consider the side effects of impotence (odds ratio (OR) = 0.40; 95% confidence interval (CI): 0.18, 0.88) and incontinence (OR = 0.27; 95% CI: 0.12, 0.63); by contrast, there was a suggestion of an opposite effect in black men, whose decision regarding surgery tended to be more strongly influenced by these side effects. CONCLUSION:
Results suggest that both clinical and social predictors play an important role for men in choosing a prostate cancer treatment, but these influences may differ by race
Association of mesenchymal cells and immunoglobulins with differentiating epithelial cells
BACKGROUND: Mesenchymal-epithelial interactions play an important role in the physiology and pathology of epithelial tissues. Mesenchymal cells either associate with epithelium basement membrane [pericytes and perivascular monocyte-derived cells (MDC)] or reside within epithelium (MDC and T cells). Although intraepithelial mesenchymal cells were suggested to contribute to the epithelium physiology, their association with particular steps in differentiation of epithelial cells, interactions among themselves, and their fate remain unclear. We studied epitopes of mesenchymal cells and their products (immunoglobulins) in stratified epithelium of uterine ectocervix, which is one of the prototypes of complete cellular differentiation from stem into the aged cells. RESULTS: Perivascular CD14 primitive MDC associated with basal (stem) epithelial cells. Thy-1 pericytes of microvasculature secreted intercellular vesicles, which associated with Ki67 postmitotic epithelial cells expressing MHC class I. Intraepithelial T cells showed an association with veiled type MDC [dendritic cell (DC) precursors] among parabasal cells, and exhibited fragmentation after entering intermediate (mature) epithelial layers. Mature DC secreted CD68 and exhibited fragmentation after reaching mid intermediate layers. Binding of IgM was detected at the top of each layer: in the upper parabasal, upper intermediate, and most surface epithelial cells. IgG was confined to the entire superficial layer. CONCLUSIONS: These data suggest that the phylogenetically and ontogenetically developed hierarchy of mesenchymal cells (MDC, pericytes, T cells) and immunoglobulins (IgM, IgG) accompanies differentiation of epithelial cells from immature into the mature and aged phenotype. Further studies of an involvement of mesenchymal cells in the regulation of tissue homeostasis may bring novel approaches to the prevention and therapy of tissue dysfunctions characterized by permanent tissue immaturity (muscular dystrophy) or accelerated aging (degenerative diseases)
A phase field crystal study of epitaxial island formation on nanomembranes
Abstract In this paper the liquid phase heteroepitaxial growth of two-dimensional strained islands on nanomembranes is examined via an amplitude expansion of a binary phase field crystal model. The maximum size that the islands can grow to coherently is shown to be strongly dependent on the nanomembrane thickness and to a lesser extent on the flux rate. For a large membrane-island misfit of about 10%, islands were found to be able to grow coherently with the membrane to almost twice as large as those grown on thick membranes (or infinite substrates). It was also found that when islands are growing on both sides of the membrane, strain relaxation in the membrane leads to more and less favorable growth regions. For thinner membranes this effect increases the degree of ordering of the islands, a result consistent with recent experimental findings
Dicyanogold Effects on Lymphokine Production
Having identified dicyanogold(I) as a common metabolite of gold-based antiarthritis drugs, we are
investigating the effects of the compound on
the production of lymphokines. Handel, et al. 1
suggested that the transcription factor AP-1, critical to the production of a number of cytokines, might
be the target for gold compounds because of a critical cysteine within its DNA binding region. Using Jurkat
cells, an established cell line as a model for CD4+
lymphocytes, we have shown that dicyanogold inhibits the binding of AP-1 to DNA and inhibits the synthesis
of IL-2 mRNA and protein. In a macrophage line, THP-1, which synthesizes IL-1β
in response to mitogen, we have shown that dicyanogold inhibits the binding of a second transcription
factor, CREB to DNA. Incubation of THP-1 cells with dicyanogold inhibits the production of IL-1β
mRNA. These results suggest that the mechanism of action of gold drugs may be through their interaction
with transcription factors necessary for the immune activation seen in Rheumatoid Arthritis
Microscopic theory of network glasses
A molecular theory of the glass transition of network forming liquids is
developed using a combination of self-consistent phonon and liquid state
approaches. Both the dynamical transition and the entropy crisis characteristic
of random first order transitions are mapped out as a function of the degree of
bonding and the density. Using a scaling relation for a soft-core model to
crudely translate the densities into temperatures, the theory predicts that the
ratio of the dynamical transition temperature to the laboratory transition
temperature rises as the degree of bonding increases, while the Kauzmann
temperature falls relative to the laboratory transition. These results indicate
why highly coordinated liquids should be "strong" while van der Waals liquids
without coordination are "fragile".Comment: slightly revised version that has been accepted for publication in
Phys. Rev. Let
Flame propagation in random media
We introduce a phase-field model to describe the dynamics of a
self-sustaining propagating combustion front within a medium of randomly
distributed reactants. Numerical simulations of this model show that a flame
front exists for reactant concentration , while its vanishing at
is consistent with mean-field percolation theory. For , we find
that the interface associated with the diffuse combustion zone exhibits kinetic
roughening characteristic of the Kardar-Parisi-Zhang equation.Comment: 4, LR541
Properties of pattern formation and selection processes in nonequilibrium systems with external fluctuations
We extend the phase field crystal method for nonequilibrium patterning to
stochastic systems with external source where transient dynamics is essential.
It was shown that at short time scales the system manifests pattern selection
processes. These processes are studied by means of the structure function
dynamics analysis. Nonequilibrium pattern-forming transitions are analyzed by
means of numerical simulations.Comment: 15 poages, 8 figure
On the predictability of chemical kinetics for the description of the combustion of simple fuels
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