QoS enhancement for adaptive streaming services over WCDMA

This paper presents a new method to adapt the quality-of-service (QoS) in a wideband code-division multiple-access (WCDMA) system, called radio network feedback (RNF). The concept of RNF is in general applicable to all the services requiring a minimum quality (i.e., non best effort) and in this paper, the focus is on streaming. In this context, RNF makes it possible for a streaming server to adapt its source bit rate to a WCDMA radio link, whose bandwidth may vary in time due, for example, to decongestion/congestion situations over the air interface or to handover. This is very beneficial for the end user as it allows to increase the bandwidth (i.e., the quality) when possible and to decrease it (instead of just dropping the service) when needed. RNF was compared with Client-based adaptation solutions. Simulation results show that RNF is fast and accurate and performs better than Client-based adaptation. For example, rebuffering occurs only with Client-based method. Moreover, with RNF the up-switch is performed only when needed, whereas the up-switch performed by means of the Client-based method is often erroneous and may annoy the end user.     

Suspended SU-8 structures for monolithic microfluidic channels

SU-8 photoresist is commonly used in the field of microfabrication as structural material or for molding of microfluidic devices. One major limitation, however, is the difficulty to process partially freestanding SU-8 structures or monolithic closed cavities and channels on-chip. We propose here a simple method for the fabrication of suspended structures, in particular of monolithic SU-8 microchannels. The method is based on the processing of a SU-8 double-layer. Appropriate modification of the optical properties of the upper layer allows for selective crosslinking in the layer sandwich. This process is suitable for versatile layouts comprising open and hollow SU-8 structures on the same chip.     

Fluorescence induction in intact spinach chloroplasts

The feces of 318 healthy adults were examined for L. monocytogenes by means of the cold enrichment and of two different selective media (nalidixic acid-trypaflavin-serum agar; Braveny medium). 15 persons (4.7 percent) proved to be carriers. Three of the 15 strains only caused hemolysis on sheep blood agar and belonged to serotypes 1/2b, 1/2c and 3c. The nonhemolytic strains without exception belonged to serotypes 4f and 4g. The Braveny medium proved to be superior to the nalidixic acid-trypaflavin-serum agar for isolating L. monocytogenes from feces.     

M‐matrices and global convergence of discontinuous neural networks

The paper considers a general class of neural networks possessing discontinuous neuron activations and neuron interconnection matrices belonging to the class of M‐matrices or H‐matrices. A number of results are established on global exponential convergence of the state and output solutions towards a unique equilibrium point. Moreover, by exploiting the presence of sliding modes, conditions are given under which convergence in finite time is guaranteed. In all cases, the exponential convergence rate, or the finite convergence time, can be quantitatively estimated on the basis of the parameters defining the neural network. As a by‐product, it is proved that the considered neural networks, although they are described by a system of differential equations with discontinuous right‐hand side, enjoy the property of uniqueness of the solution starting at a given initial condition. The results are proved by a generalized Lyapunov‐like approach and by using tools from the theory of differential equations with discontinuous right‐hand side. At the core of the approach is a basic lemma, which holds under the assumption of M‐matrices or H‐matrices, and enables to study the limiting behaviour of a suitably defined distance between any pair of solutions to the neural network. Copyright © 2006 John Wiley & Sons, Ltd.     

Interlaboratory Test of Exhaust PM Using ELPI

Abstract

The Particulate Measurement Programme (PMP) works on the development of an improved method for the exhaust particulate matter (PM) measurement, which can include, if feasible and necessary, the measurement of particle number. The French PMP subgroup, composed of IFP, PSA Peugeot-Citroën, Renault, and UTAC, has defined a measurement protocol based on electrical low-pressure impactor (ELPI) and conducted an interlaboratory test to evaluate its performances. The technical program was based on tests carried out on three Euro3 passenger cars (one gasoline operating under stoichiometric conditions, one Diesel, and one Diesel equipped with a diesel particulate filter (DPF)) that were tested on the New European Driving Cycle (NEDC). The regulated pollutants are also measured, as indicators of test repeatability and good working conditions. The interlaboratory reproducibility value of the tunnel background tests is quite high (337%) due to low particle numbers. The repeatability values increase at low particle numbers independently of the vehicle used. On the NEDC, the reproducibility of total particle number is 59, 47, and 131% for the gasoline, Diesel, and DPF-equipped Diesel vehicles, respectively (compare to 67, 29, and 164% for PM collected on filters). These results show that the protocol used in this study allows a reliable measurement of exhaust particle number in the case of vehicles emitting at least two orders of magnitude more than the tunnel background. In the other cases, the measurement variability is too high, especially for regulatory purposes, without taking into account other metrological aspects, such as calibration.     

Early cyclosporine monotherapy in liver transplantation: a 5-year follow-up of a prospective, randomized trial

Maintenance of adequate immunosuppression and avoidance of side-effects are the goals of long-term management of all organ-transplanted patients. We here report the final results of a prospective, randomized trial comparing early cyclosporine monotherapy versus double-drug therapy (cyclosporine and steroids) in adult liver transplantation patients. One hundred four patients were randomized 3 months after transplantation either to continue (Group I = 50 patients) or to stop steroids (Group II = 54 patients). Patients on a double-drug regimen were maintained long term on methylprednisolone at a dose of 0.1 mg/kg/d. Target cyclosporine trough levels were between 150 and 250 ng/mL in both groups. Our main points of interest were the prevalence of acute and chronic rejections and steroid-related side-effects in the two groups of patients. Mean follow-up was 41 +/- 16 months (range, 4-68 months). Patient actuarial survival 2 and 5 years after randomization was similar in the two groups (82% vs. 83% and 82% vs. 77%). The prevalence of acute rejections after randomization was, respectively, 8% and 4%. A single episode of chronic rejection was observed only in a patient on long-term steroid therapy. Side-effects of steroid therapy were less frequent in patients weaned off steroids, and when considering hypertension and diabetes, the differences between the two groups were statistically significant. Early cyclosporine monotherapy is a safe undertaking in liver transplantation because it allows a significant reduction of steroid-related side-effects without increasing the risk of acute and chronic rejection. After 5 years, patient survival was similar in patients with or without steroids.     

1,4-Dioxane enhances properties and biocompatibility of polyanionic collagen for tissue engineering applications

Polyanionic collagen obtained from bovine pericardial tissue submitted to alkaline hydrolysis is an acellular matrix with strong potential in tissue engineering. However, increasing the carboxyl content reduces fibril formation and thermal stability compared to the native tissues. In the present work, we propose a chemical protocol based on the association of alkaline hydrolysis with 1,4-dioxane treatment to either attenuate or revert the drastic structural modifications promoted by alkaline treatments. For the characterization of the polyanionic membranes treated with 1,4-dioxane, we found that (1) scanning electron microscopy (SEM) shows a stronger reorientation and aggregation of collagen microfibrils; (2) histological evaluation reveals recovering of the alignment of collagen fibers and reassociation with elastic fibers; (3) differential scanning calorimetry (DSC) shows an increase in thermal stability; and (4) in biocompatibility assays there is a normal attachment, morphology and proliferation associated with high survival of the mouse fibroblast cell line NIH3T3 in reconstituted membranes, which behave as native membranes. Our conclusions reinforce the ability of 1,4-dioxane to enhance the properties of negatively charged polyanionic collagen associated with its potential use as biomaterials for grafting, cationic drug- or cell-delivery systems and for the coating of cardiovascular devices.     

Erectile dysfunction of vasculogenic origin: ultrastructural evaluation of cavernous myo-endothelial unit as prognostic index of penile revascularization]

1. The present study examined the effects of various agents on high calcium-induced relaxation of the rabbit thoracic aorta precontracted by phenylephrine (0.1 microM) or KCl (30 mM). 2. The vascular smooth muscle relaxation caused by high calcium was not changed in the presence of endothelium, glibenclamide (3 microM), TEA (5 mM), verapamil (1 microM), lidocaine (0.1 mM) and vanadate (0.1 mM). 3. In the presence of ouabain (0.1 mM) or potassium-free medium, high calcium-induced relaxation was completely abolished. 4. When rings were precontracted by high concentrations of phenylephrine (1 microM, 10 microM) and KCl (30 mM, 45 mM, 60 mM), calcium-induced relaxation was gradually decreased. 5. A low concentration of calcium ionophore A-23187 (0.1 microM) did not change calcium-induced relaxation, but A-23187 at a high concentration (1 microM) depressed this relaxation. 6. These results suggest that Na-K-ATPase activation could be responsible for high calcium-induced relaxation.