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The use of systemic corticosteroids in debilitating sycosis barbae, sycosis barbae fulminans
No full textSubmitted as: (mark with X) X_Case Report _Case Presentation _Photo Vignette _Letter Authors declare that the contents of this article are their own original unpublished findings. Title: The use of systemic corticosteroids in debilitating sycosis barbae, sycosis barbae fulminans Authors: Kathleen R Krivda MD, Uzoamaka J Okoro MD, Nicholas F Logemann DO Affiliations: Department of Dermatology, Walter Reed National Military Medical Center, Bethesda, Bethesda, Maryland, USA Corresponding Author: Kathleen Krivda MD, Walter Reed National Military Medical Center, 8901 Rockville Pike, Bethesda MD 20889, Tel: 240-751-3823, Email: [email protected] Abstract (no more than 200 words)
The optimization and validation of HPLC method for determination of triamcinolone acetonide in topical pharmaceutical product
No full textAuthor: Krivda A. Title: The optimalisation and validation of HPLC method for determination of triamcinolone acetonide in topical pharmaceutical product Language: Czech Keywords: HPLC Triamcinolone acetonide Triamcinolone Methylparaben Propylparaben Validation A novel reversed-phase high-performance liquid chromatography (RP-HPLC) method was developed and validated for the determination of active component triamcinolone acetonide, its degradation product triamcinolone and two preservatives presented in the cream - methylparaben and propylparaben, using estradiole as an internal standard. The chromatographic separation was performed on a Supelco Discovery HSF5 column. The mobile phase for separation of all compounds consists of a mixture of acetonitrile and water (45:55 v/v). The analysis time was less than 9 minutes, at a flow rate of 0,6 ml/min and detection at 240 nm. The method was found to be appicable for routine analysis (stability tests, homogeneity) in the pharmaceutical product topical cream Triamcinolone cream 0,1%
Migrating to a sustainable energy system: Distributed generation and storage, fuel cells and hypercars
No full textThis paper examines a number of issues in sustainable energy generation and distribution, and explores avenues that are available for integration of our society’s energy supplies. In particular, the paper presents a way in which transport vehicle energy supplies could be integrated with distributed generation schemes to achieve synergistic and beneficial outcomes. The worldwide energy system contains fundamental problems that result directly from the use of unsustainable fuels and a lack of energy system integration. There is a need to adopt an integrated, sustainable energy system for our society.\ud
The adoption of distributed generation could result in beneficial restructuring of the energy trade, and a change in the role of energy providers. Inherent benefits in distributed generation schemes would directly combat barriers to installation of renewable generation facilities, which might prove distributed renewable energy sources to be more feasible. The presence of fuel cells, batteries, power electronic inverters and intelligent controls in vehicles of the future provides many opportunities for the integration of vehicle energy supplies into a distributed generation scheme. In such a system, vehicles could play a major role in power generation and storage
Supporting the Electromechanical Nature of Ultra-Fast Charge Pulses in Insulating Polymer Conduction
No full textThe generation and transport of ultra-fast charge
pulses is a new conduction mechanism in insulating polymers,
which is related to the electromechanical property of polymers.
An investigation of fast space charge dynamics in pure and
nanofilled epoxy resin at different temperatures is presented in
this paper. Experimental observations show the appearance of
ultra-fast charge pulses, which cause heterocharge
accumulation at electrodes. Mobility and repetition rate of both
positive and negative fast pulses decrease with increasing
nanoparticle concentration. Their temperature dependence was
also determined. The influence of nanoparticles on dynamicmechanical properties is studied to investigate the relation
between charge dynamics and the chain relaxations. The values
of activation energy for pulse mobility, repetition rate and loss
modulus support the speculation that in epoxy based
nanocomposite the mechanism of the ultra-fast charge pulse
injection is associated with the β mechanical relaxation.
Transport of positive pulses seems to be governed by the same
mechanical relaxation as injection, while the transport of
negative pulses is probably driven by a different process. An
explanation for the variation of fast charge pulse characteristics
is given in terms of the different morphological effects of
nanoparticles on epoxy resin
Recognition of discharges: Discrimination and classification
No full textElectrical Engineering, Mathematics and Computer Scienc
Sestava novele Blažena krivda Edvarda Kocbeka
No full textWith the novelettes from Kocbek\u27s collection Strah in pogum (Fear and Courage) existential philosophy emerged in Slovene literature. The author not only expressed his aesthetic, philosophical and other ideas only indirectly, but he at the same time opened up the problem of moral and ideological conflicts, which pushed his heroes into an existential anguish. All of this is reflected also in the structure of his narrative
A New Ultra Fast Conduction Mechanism in Insulating Polymer Nanocomposites
No full textA brand new phenomenon, namely, electrical conduction via soliton-like ultra fast space charge pulses, recently identified in unfilled cross-linked polyethylene, is shown for the first time to occur in insulating polymer nanocomposites and its characteristics correlated with the electromechanical properties of nanostructured materials. These charge pulses are observed to cross the insulation under low electrical field in epoxy-based nanocomposites containing nanosilica particles with relative weights of 1%, 5%, 10%, and 20% at speeds orders of magnitude higher than those expected for carriers in insulating polymers. The characteristics of mobility, magnitude and repetition rate for both positive and negative charge pulses are studied in relation to nanofiller concentration. The results show that the ultra fast charge pulses (packets) are affected significantly by the concentration of nanoparticles. An explanation is presented in terms of a new conduction mechanism where the mechanical properties of the polymer and movement of polymer chains play an important role in the injection and transport of charge in the form of pulses. Here, the charge transport is not controlled by traps. Instead, it is driven by the contribution of polarization and the resultant electromechanical compression, which is substantially affected by the introduction of nanoparticles into the base polymer
Laser ablation of silicone composites
No full textSilicone rubber based composites are used widely for outdoor high voltage components such as bushings, cable strings and as weather resistant coatings. In adverse weather conditions, dry band discharges [1] can occur resulting in tracking and surface damage; this can ultimately result in dielectric or mechanical failure. Traditionally these components are filled with aluminium trihydrate (ATH) and other fillers, such as silica, to improve their tracking resistance and erosion performance [2]. It is important in designing such materials that good arc resistant composites are chosen in order to maximise lifetime and minimise downtime and maintenance costs. Inclined plane tracking tests [2] have proved useful in determining the relative resistance of different material formulations to surface damage and have indicated that materials having a high filler loading are beneficial up to the point where a good dispersion of the filler can be maintained. An alternative test method is to use a high power laser to apply a known amount of energy at a known power to a localised region of the sample. Recently, this technique has been successfully applied to the characterisation of several outdoor insulation materials [3], however in these experiments we have sought to compare different materials rather than a fixed material having different filler contents. In the current investigation we consider the role of the filler content on the ablation resistance of several silicone rubber based composites, a range of laser powers and energies were employed and the resulting surface damage was quantified by pit-depth and mass loss measurements supplemented by optical microscopy. The extent of ablation was correlated to the filler content and composition and pointers to improved materials provided
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