Significant Reduction of Antibiotic Use in the Community after a Nationwide Campaign in France, 2002–2007

Didier Guillemot and colleagues describe the evaluation of a nationwide programme in France aimed at decreasing unnecessary outpatient prescriptions for antibiotics. The campaign was successful, particularly in reducing prescriptions for children

Poor adherence to antibiotic prescribing guidelines in acute otitis media—obstacles, implications, and possible solutions

Many countries now have guidelines on the clinical management of acute otitis media. In almost all, the public health goal of containing acquired resistance in bacteria through reduced antibiotic prescribing is the main aim and basis for recommendations. Despite some partial short-term successes, clinical activity databases and opinion surveys suggest that such restrictive guidelines are not followed closely, so this aim is not achieved. Radical new solutions are needed to tackle irrationalities in healthcare systems which set the short-term physician–patient relationship against long-term public health. Resolving this opposition will require comprehensive policy appraisal and co-ordinated actions at many levels, not just dissemination of evidence and promotion of guidelines. The inappropriate clinical rationales that underpin non-compliance with guidelines can be questioned by evidence, but also need specific developments promoting alternative solutions, within a framework of whole-system thinking. Promising developments would be (a) physician training modules on age-appropriate analgesia and on detection plus referral of rare complications like mastoiditis, and (b) vaccination against the most common and serious bacterial pathogens

Transient Analysis of Collector Current Collapse In Power HBTs

This paper describes the dynamic of the current collapse phenomenon that can occur in a multifinger power HBT. The electrothermal model used is a self consistent model based on an electrical distributed Ebers Moll model coupled to a thermal subcircuit derived from Ritz vector reduction technique of 3D thermal finite element simulation. Simulation of static as well as dynamic collector current collapse for HBT has been performed and allows to optimize the ballast resistor

Electrothermal harmonic balance simulation of an INGAP/GAAS HBT based on 3D thermal and semiconductor transport models

A parallel implementation of the direct coupling of InGaP/GaAs HBT transport equations has been included in an Harmonic Balance simulator. Several results such as a class AB amplifier for mobile communication study and a stability analysis of “crunch effect” in multi-finger HBT have been performed

Spice Thermal Subcircuit of Multifinger HBT derived from Ritz Vector reduction technique of 3D Thermal Simulation for electrothermal modeling

This paper deals with the integration of a reduced thermal model based on tree dimensional Finite Element (FE) thermal simulation into circuit simulator for accurate prediction of electrothermal behavior of power devices. The reduced thermal model based on the Ritz vectors approach is easily usable in any kind of circuit simulator because it is described by a spice format subcircuit. The model has been successfully experimented with the ADS simulator. Electrical based thermal measurements of transient temperature response have successfully validated our approach

New trends in characterization and modeling of High Power devices

In this paper, we present some non exhaustive measurement techniques used for characterization and modeling of high power devices. Capabilities offered by pulsed measurements can be an efficient approach to deal with self-heating effects and sometimes trapping effects encountered in microwave high power devices. Pulsed techniques allow to separate self-heating and trapping effects, making like this the modeling process easier. A pulsed RF and pulsed bias load-pull system is then described as well as a time waveform measurement system. Capabilities of these two characterization tools are illustrated with results obtained on a high power silicon bipolar transistor and on a GaAs MESFET device

A direct coupling between the semiconductor equations describing a GaInP/GaAs HBT in a circuit simulator for the co-design of microwave devices and circuits

This paper describes the direct coupling between a physical device simulator and a circuit simulator based on the Harmonic Balance (Hit) technique. The semiconductor device equations adopted concern a GaInP/GaAs HBT for power applications. A full computation of the Jacobian matrix for convergence improvement has been implemented. It provides us with a powerful tool for the codesign of devices and circuits which has been successfully tested to simulate the power transfer characteristic of a device operating in class AB