An image quality comparison of standard and dual-side read CR systems for pediatric radiology.

An objective analysis of image quality parameters was performed for a computed radiography (CR) system using both standard single-side and prototype dual-side read plates. The pre-sampled modulation transfer function (MTF), noise power spectrum (NPS), and detective quantum efficiency (DQE) for the systems were determined at three different beam qualities representative of pediatric chest radiography, at an entrance detector air kerma of 5 microGy. The NPS and DQE measurements were realized under clinically relevant x-ray spectra for pediatric radiology, including x-ray scatter radiations. Compared to the standard single-side read system, the MTF for the dual-side read system is reduced, but this is offset by a significant decrease in image noise, resulting in a marked increase in DQE (+40%) in the low spatial frequency range. Thus, for the same image quality, the new technology permits the CR system to be used at a reduced dose level.

Un partenariat public-privé rigide ou flexible ? Théorie et application aux concessions routières à péage

In this article, we explore the contractual design of toll road concession contracts. We highlight the fact that contracting parties try to sign not only complete rigid contracts in order to avoid renegotiations but also flexible contracts in order to adapt contractual framework to contingencies and to create incentives for cooperative behavior. This gives rise to multiple toll adjustment provisions and to a tradeoff between rigid and flexible contracts. Such a tradeoff is formalized using an incomplete contract framework - including ex post maladaptation and renegotiation costs - and propositions are tested using an original database of 71 concession contracts. Our results suggest an important role for economic efficiency concerns, as well as politics, in designing such public-private contracts. Codes JEL : D23, H11, H54, L14, L9.

Animal model to compare the effects of suture technique on cross-sectional compliance on end-to-side anastomoses.

OBJECTIVE: An animal model has been developed to compare the effects of suture technique on the luminal dimensions and compliance of end-to-side vascular anastomoses. METHODS: Carotid and internal mammalian arteries (IMAs) were exposed in three pigs (90 kg). IMAs were sectioned distally to perform end-to-side anastomoses on carotid arteries. One anastomosis was performed with 7/0 polypropylene running suture. The other was performed with the automated suture delivery device (Perclose/Abbott Labs Inc.) that makes a 7/0 polypropylene interrupted suture. Four piezoelectric crystals were sutured on toe, heel and both lateral sides of each anastomosis to measure anastomotic axes. Anastomotic cross-sectional area (CSAA) was calculated with: CSAA = pi x mM/4 where m and M are the minor and major axes of the elliptical anastomosis. Cross-sectional anastomotic compliance (CSAC) was calculated as CSAC=Delta CSAA/Delta P where Delta P is the mean pulse pressure and Delta CSAA is the mean CSAA during cardiac cycle. RESULTS: We collected a total of 1200000 pressure-length data per animal. For running suture we had a mean systolic CSAA of 26.94+/-0.4 mm(2) and a mean CSAA in diastole of 26.30+/-0.5 mm(2) (mean Delta CSAA was 0.64 mm(2)). CSAC for running suture was 4.5 x 10(-6)m(2)/kPa. For interrupted suture we had a mean CSAA in systole of 21.98+/-0.2 mm(2) and a mean CSAA in diastole of 17.38+/-0.3 mm(2) (mean Delta CSAA was 4.6+/-0.1 mm(2)). CSAC for interrupted suture was 11 x 10(-6) m(2)/kPa. CONCLUSIONS: This model, even with some limitations, can be a reliable source of information improving the outcome of vascular anastomoses. The study demonstrates that suture technique has a substantial effect on cross-sectional anastomotic compliance of end-to-side anastomoses. Interrupted suture may maximise the anastomotic lumen and provides a considerably higher CSAC than continuous suture, that reduces flow turbulence, shear stress and intimal hyperplasia. The Heartflo anastomosis device is a reliable instrument that facilitates performance of interrupted suture anastomoses.

Sweerts sur Georges Lévy, 750 cmc [course motocycliste Paris-Reims-Paris, side-car, 6 juillet 1919] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 54748

Boutet sur Rover, side-car 500 cmc [course motocycliste Paris-Reims-Paris, 6 juillet 1919] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 54749

[Concurrent de la course motocycliste Paris-Reims-Paris, conduisant un side-car Rover, 6 juillet 1919] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 54751

Sistema de control ambiental flexible per a la indústria agroalimentària (SCAFIA)

El present treball està basat en el desenvolupament d¿un sistema que permeti fer una demostració pràctica i útil amb els materials que l¿àrea de sistemes encastats posa a la nostra disposició. De forma resumida es tracta de motes/nodes amb possibilitat de comunicació inhalàmbrica entre ells i un sistema operatiu TinyOS programable amb el llenguatge nesC.

6.7.19, Paris-Reims-Paris, Catelle Georges (25) sur Lévy et Le Pen (26) sur Lévy à l'arrivée [en side-cars] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 54768

Catellas/Georges Leroy, 750 cm3 [le side-car n° 25 au départ de la course Paris-Reims-Paris] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 54754

Lecomte sur Rover, 500 cmc [course motocycliste Paris-Reims-Paris, side-car, 6 juillet 1919] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 54746

In vivo assessment of antiretroviral therapy-associated side effects

Antiretroviral therapy has been associated with side effects, either from the drug itself or in conjunction with the effects of human immunodeficiency virus infection. Here, we evaluated the side effects of the protease inhibitor (PI) indinavir in hamsters consuming a normal or high-fat diet. Indinavir treatment increased the hamster death rate and resulted in an increase in triglyceride, cholesterol and glucose serum levels and a reduction in anti-oxLDL auto-antibodies. The treatment led to histopathological alterations of the kidney and the heart. These results suggest that hamsters are an interesting model for the study of the side effects of antiretroviral drugs, such as PIs.

[Paul] Péan, sur Peugeot [course Paris-Reims-Paris, moto 6 HP avec side-car, 6 juillet 1919] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 54734

A mixed H2/H∞-based semiactive control for vibration mitigation in flexible structures

In this paper, we address this problem through the design of a semiactive controller based on the mixed H2/H∞ control theory. The vibrations caused by the seismic motions are mitigated by a semiactive damper installed in the bottom of the structure. It is meant by semiactive damper, a device that absorbs but cannot inject energy into the system. Sufficient conditions for the design of a desired control are given in terms of linear matrix inequalities (LMIs). A controller that guarantees asymptotic stability and a mixed H2/H∞ performance is then developed. An algorithm is proposed to handle the semiactive nature of the actuator. The performance of the controller is experimentally evaluated in a real-time hybrid testing facility that consists of a physical specimen (a small-scale magnetorheological damper) and a numerical model (a large-scale three-story building)

Pasola sur A.J. S. [le side-car n° 31 au départ de la course Paris-Reims-Paris] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 54756