[Preferences of general practitioners in metropolitan France with regard to the delegation of medico-administrative tasks to secretaries assisting medico-social workers: Study in conjoint analysis]. / Préférences des médecins généralistes libéraux en France métropolitaine quant à la délégation des tâches médico-administratives aux secrétaires assistant(e)s médico-social(e)s : étude en analyse conjointe.

BACKGROUND: A general practitioner's office is an economic unit where task delegation is an essential component in improving the quality and performance of work. AIM: To classify the preferences of general practitioners regarding the delegation of medical-administrative tasks to assistant medical-social secretaries. METHOD: Conjoint analysis was applied to a random sample of 175 general practitioners working in metropolitan France. Ten scenarios were constructed based on seven attributes: training for medical secretaries, logistical support during the consultation, delegation of management planning, medical records, accounting, maintenance, and taking initiative on the telephone. A factorial design was used to reduce the number of scenarios. Physicians' socio-demographic variables were collected. RESULTS: One hundred and three physicians responded and the analysis included 90 respondents respecting the transitivity of preferences hypothesis. Perceived difficulty was scored 2.8 out of 5. The high rates of respondents (59%; 95% CI [51.7-66.3]) and transitivity (87.5%; 95% CI [81.1-93.9]) showed physicians' interest in this topic. Delegation of tasks concerning management planning (OR=2.91; 95% CI [2.40-13.52]) and medical records (OR=1.88; 95% CI [1.56-2.27]) were the two most important attributes for physicians. The only variable for which the choice of a secretary was not taken into account was logistical support. CONCLUSION: This is a first study examining the choices of general practitioners concerning the delegation of tasks to assistants. These findings are helpful to better understand the determinants of practitioners' choices in delegating certain tasks or not. They reveal doctors' desire to limit their ancillary tasks in order to favor better use of time for "medical" tasks. They also expose interest for training medical secretaries and widening their field of competence, suggesting the emergence of a new professional occupation that could be called "medical assistant".

Real-time software platform design for in-vivo navigation of a small ferromagnetic device in a swine carotid artery using a magnetic resonance imaging system.

Using an 1.5T Siemens clinical Magnetic Resonance Imaging system (MRI), a 1.5 mm diameter ferromagnetic bead is moved across a pre-planned path in the carotid artery of a 25 kg living swine. The software architecture for the navigation and path planning is herein described. Using the real-time feedback capabilities of recent MRIs, the device is moved, controlled and tracked using the magnetic gradients coils already present for imaging purposes. Navigation of the ferromagnetic device has been achieved with a peak velocity of about 13 cm/s through a set of pre established 11 waypoints. The dedicated software architecture presented in this paper lies in a modified real-time MRI imaging sequence. The dedicated architecture permits the navigation of the ferromagnetic bead with an operating frequency of 24 Hz Real-time control of the magnetic core is achieved through the implementation of a simple 2D PID controller incorporated in the presented software platform.

Sequence design and software environment for real-time navigation of a wireless ferromagnetic device using MRI system and single echo 3D tracking.

Software architecture for the navigation of a ferromagnetic untethered device in a 1D and 2D phantom environment is briefly described. Navigation is achieved using the real-time capabilities of a Siemens 1.5 T Avanto MRI system coupled with a dedicated software environment and a specially developed 3D tracking pulse sequence. Real-time control of the magnetic core is executed through the implementation of a simple PID controller. 1D and 2D experimental results are presented.

Real-time Magnetic Resonance Gradient-based Propulsion of a Wireless Microdevice Using Pre-Acquired Roadmap and Dedicated Software Architecture.

A new method for the propulsion of a spherical ferromagnetic device along a given path in a water filled phantom with no human interaction is presented using an 1.5 T Magnetic Resonance Imaging (MRI) clinical system. A special real time loop is implemented and presented that feeds the scanner with the appropriate gradients amplitudes and directions based on a pre-determined path. This paper studies the necessary propulsion conditions and limitations such as device dimensions and necessary gradient amplitude as well as overall latency problems such as communication delays and computation delays needed to achieve precise propulsion. It also presents a dedicated software environment for path control and validation, propulsion and tracking of such device.

Corrosion protection of metal implants by hard biocompatible ceramic coatings deposited by radio-frequency sputtering.

Most metals used for orthopaedic and stomatology implants and prostheses belong to the families of titanium or nickel-based and cobalt-based superalloys designed for advanced technology industries (e.g. space, aeronautic and nuclear industries). Ideal materials should be as insoluble and biologically compatible as possible. In the present paper the corrosion behaviour of Ni-Cr and Co-Cr alloys in biological media is evaluated through potentiodynamic polarization tests. It is shown that these metals exhibit some minor release of the component elements and degradation products, which may induce cytotoxic and allergic effects. The corrosion resistance of these alloys can be strongly enhanced by hard ceramic coatings deposited by radio-frequency sputtering. The biocompatibility of coated and uncoated metals is compared from differentiated human cell cultures.