Promotion of wound healing by Plantago major L. leaf extracts – ex-vivo experiments confirm experiences from traditional medicine

The wound-healing properties of Plantago major L. (plantain) were evaluated using an ex-vivo porcine wound-healing model. Ethanol- and water-based extracts were prepared from greenhouse-grown and freeze-dried leaves of P. major. Both types of extracts stimulated wound healing in porcine skin, but the ethanol-based extracts had a somewhat stronger effect. A concentration of 1.0 mg/mL (on dry weight basis) produced the best results for both types of extracts.     

Interpretation of Lagrange multipliers in nonlinear pricing problem

We present well-known interpretations of Lagrange multipliers in physical and economic applications, and introduce a new interpretation in nonlinear pricing problem. The multipliers can be interpreted as a network of directed flows between the buyer types. The structure of the digraph and the fact that the multipliers usually have distinctive values can be used in solving the optimization problem more efficiently. We also find that the multipliers satisfy a conservation law for each node in the digraph, and the non-uniqueness of the multipliers are connected to the stability of the solution structure.     

Liquid chromatography tandem mass spectrometry determination of total budesonide levels in dog plasma after inhalation exposure

A sensitive and selective method to quantify budesonide in dog plasma samples was developed and fully validated. Liquid–liquid extraction was followed by solid-phase extraction and liquid chromatography–tandem mass spectrometry with electrospray ionization. After reconstitution of the analytes in the mobile phase, samples were analysed by reversed-phase liquid chromatography with isocratic elution. d8-Budesonide was used as an internal standard, and characteristic transitions of d8-budesonide and budesonide were used for quantification. The method was validated with respect to selectivity, specificity, linearity, recovery, repeatability, reproducibility and limits of detection and quantification. The validated method was successfully applied to monitor the plasma levels of budesonide in dogs exposed to clinical doses of inhaled and intravenous drug.     

Dense Packing of Patterns in a Permutation

We study the length L _k of the shortest permutation containing all patterns of length k. We establish the bounds e ⁻² k ² < L _k ≤ (2/3 + o(1))k ². We also prove that as k → ∞, there are permutations of length (1/4 + o(1))k ² containing almost all patterns of length k. Received January 2, 2007     

All-Printed Green Micro-Supercapacitors Based on a Natural-derived Ionic Liquid for Flexible Transient Electronics

The fabrication and characterization of green, flexible, and ultra-thin supercapacitors that are able to operate above 1.5 V is reported, using an all-printed fabrication process. The devices are produced by aqueous spray casting of a natural-derived electrolyte ionogel composed by 2-hydroxyethyl cellulose and by the ionic liquid choline lactate, while the electrodes are composed of highly porous nanostructured carbon films deposited by supersonic cluster beam deposition (SCBD). The obtained supercapacitors (device thickness < 10 μm) are stable to bending and they possess power values up to 120 kW kg^–1. The combination of aqueous spray casting and SCBD constitutes a versatile, scalable, and eco-friendly fabrication process able to directly print interconnected elements suitable for transient electronic systems.     

Dark Supersymmetry

We propose a model of Dark Supersymmetry, where a supersymmetric dark sector is coupled to the classically scale invariant non-supersymmetric Standard Model through the Higgs portal. The dark sector contains a mass scale that is protected against radiative corrections by supersymmetry, and the portal coupling mediates this scale to the Standard Model, resulting in a vacuum expectation value for the Higgs field and the usual electroweak symmetry breaking mechanism. The supersymmetric dark sector contains dark matter candidates, and we show that the observed dark matter abundance is generated for a natural choice of parameters, while avoiding the current experimental bounds on direct detection. Future experiments can probe this scenario if the dark sector mass scale is not too high.     

Self-aligned patterning method of poly(aniline) for organic field-effect transistor gate electrode

We present a new manufacturing method for the bottom-gate type organic field-effect transistor (OFET) having a self-aligned gate electrode based on conducting poly(aniline). This method utilizes the possibility to turn the insulating emeraldine base (PANI-EB) form of poly(aniline) into the conducting emeraldine salt (PANI-ES) form by using UV exposure and photoacid generator (PAG) material. When the source–drain electrodes are used as the mask layer in the UV exposure step an optimal alignment between the gate electrode and source–drain electrodes can be reached, and the parasitic capacitance of the transistor can be minimized. We anticipate that the proposed concept also simplifies the fabrication of the transistors since no additional processing of the photoresist layers is needed to pattern the gate electrode or the gate insulator layer.     

Tick size and stock returns

Tick size is an important aspect of the micro-structural level organization of financial markets. It is the smallest institutionally allowed price increment, has a direct bearing on the bid-ask spread, influences the strategy of trading order placement in electronic markets, affects the price formation mechanism, and appears to be related to the long-term memory of volatility clustering. In this paper we investigate the impact of tick size on stock returns. We start with a simple simulation to demonstrate how continuous returns become distorted after confining the price to a discrete grid governed by the tick size. We then move on to a novel experimental set-up that combines decimalization pilot programs and cross-listed stocks in New York and Toronto. This allows us to observe a set of stocks traded simultaneously under two different ticks while holding all security-specific characteristics fixed. We then study the normality of the return distributions and carry out fits to the chosen distribution models. Our empirical findings are somewhat mixed and in some cases appear to challenge the simulation results.     

Controlling the precision of estimated means in interactive simulation

The computing power of modern workstations has made it possible to simulate many queueing systems interactively. Recent development in simulation software has mainly concentrated on interactive facilities. Unfortunately the precision of estimates has widely been overlooked in interactive simulation. In this paper we propose a method for controlling the precision of estimated means during an interactive simulation run. Since in a typical situation of interactive simulation the user is simultaneously interested in several means, we consider both the simultaneous precision and individual precisions of the estimated means. The method is based on the existing methods for estimating standard errors and on the Bonferroni inequality. The Bonferroni inequality is used to obtain a lower bound for the simultaneous precision.