Vertical profiles of particle mass concentration in the urban canopy above the city of Lyon have been obtained from Lidar measurements of atmospheric backscattering, over a period of three days. The concentrations measured at 50 m above the ground have been compared with the mass concentration of PM10 measured by a ground-based sampler located near the Lidar site. At certain times during the measurement campaign, the Lidar concentration measurements at 50 m agree reasonably well with the concentrations at ground level but at other times the differences between the two sets of measurements are so great that they cannot be explained by possible uncertainties in the data processing. Even when the Lidar and ground-based measurements coincide, there are significant differences between the two signals. To explain these differences we have computed the trajectories of the air parcels that pass over the Lidar, using a numerical model for the wind field that takes into account surface features such as relief and changes in roughness. This analysis showed that the differences can be explained by the meteorological conditions (wind speed and direction, vertical profiles of temperature) and the positions of the different sources of particulate matter relative to the measurement site. The combination of Lidar, ground-based sampler and air mass trajectory calculations is shown to be a powerful tool for discriminating between different sources of pollution, which could be useful in enforcing an urban air quality policy.

La voltige aerienne est un sport dont la pratique est a l'origine de contraintes physiologiques multiples, principalement cardiovasculaires avec, en cas d'inadaptation, un risque d'incapacite subite en vol, susceptible de mettre en jeu la securite aerienne et justifiant la selection et le suivi des pilotes. Les contraintes aeronautiques au cours du vol sont multiples, liees au milieu traverse, au fonctionnement de l'avion et aux mouvements de l'aeronef. Ceux-ci creent des accelerations (+ Gz en particulier) qui posent le probleme de leur tolerance hemodynamique car pouvant induire une perte de connaissance par hypoxie cerebrale. La tolerance des accelerations est variable selon les individus; elle peut etre amelioree par l'entrainement, par certaines manœuvres de protection, et sont diminuees par l'hypoxie, les medicaments, la deshydratation, la chaleur. Par ailleurs, en voltige aerienne, certaines figures diminuent egalement cette tolerance aux accelerations + Gz. C'est l'effet push-pull (acceleration - Gz suivie d'une acceleration + Gz immediate). Cela entraine un risque de perte de connaissance brutale pour un facteur de charge tres inferieur a celui que le pilote se sait capable de supporter. En dehors des effets hemodynamiques, l'existence d'une veritable cardiomyopathie des accelerations etait suggeree, mais elle n'a pas ete prouvee chez l'homme. Enfin, si les modifications du rythme cardiaque lors des accelerations sont habituelles et liees aux modifications de la balance vagosympathique, les troubles du rythme ventriculaire et supraventriculaire sont rares et lies a l'intensite et a la duree de l'acceleration.

L'émergence d'une nouvelle technique de détection non invasive des lésions coronaires comme le scanner coronaire multicoupes, fait poser la question de son utilisation pour le dépistage, surtout en cas de faillite des moyens habituels.

INTRODUCTION:The association of vasoplegic shock and myocardial infarction in a patient under iloprost treatment for critical ischemia of the lower limbs has not previously been reported.OBSERVATION:A 56 year-old man suffering from type 2 diabetes, hypertension and dyslipidemia developed critical ischemia of the right leg and was treated with iloprost. On the 19th day of infusion, he developed a vasoplegic shock with myocardial infarction. The shock resolved and he recovered from the infarction.DISCUSSION:This case report indicates the need for reinforced blood pressure and electrocardiographic monitoring in diabetes patients treated with iloprost.

Aerobatics is an aerial sport which has many physiological constraints, principally cardiovascular, with a risk if not adapted of sudden mid-air incapacity which could jeopardise aviation safety, and thus justifies the selection and surveillance of pilots. The aeronautical constraints during flight are multiple, related to the environment traversed, how the aircraft functions and its movements. Those which cause accelerations (+G in particular) pose the problem of haemodynamic tolerance because they can induce loss of consciousness due to cerebral hypoxia. Tolerance of acceleration varies among individuals; it can be improved with training, certain protective manoeuvres, and is reduced by hypoxia, certain medications, dehydration and heat. Moreover, in aerobatics certain tricks require manoeuvres which reduce this tolerance to +G accelerations. This is the "push-pull" effect (_G acceleration immediately followed by +G acceleration). This leads to a risk of sudden loss of consciousness with a load factor much lower than that which the pilot knows he is capable of tolerating. Besides the haemodynamic effects, the existence of an actual acceleration cardiomyopathy has been suggested but has not been proven in man. Finally, while changes in cardiac rhythm during accelerations are usual and relate to changes in vaso-sympathetic balance, ventricular and supra-ventricular rhythm disturbances are rare and are related to the intensity and duration of the acceleration.

Introduction The association of vasoplegic shock and myocardial infarction in a patient under iloprost treatment for critical ischemia of the lower limbs has not previously been reported.Observation A 56 year-old man suffering from type 2 diabetes, hypertension and dyslipidemia developed critical ischemia of the right leg and was treated with iloprost. On the 19(th) day of infusion, he developed a vasoplegic shock with myocardial infarction. The shock resolved and he recovered from the infarction.Discussion This case report indicates the need for reinforced blood pressure and electrocardiographic monitoring in diabetes patients treated with iloprost.

UNLABELLEDMultislice computed tomography (MSCT) is a non-invasive and validated technique to detect coronary stenoses. Some questions remain about its accuracy to detect coronary stenoses (CS), especially for asymptomatic patients (P) when a prior stress test isn't conclusive.METHODSMSCT was performed among 45 asymptomatic men (mean age: 58,3 +/- 16), with a high ten year risk of fatal cardiovascular disease (SCORE 2003 data for low-risk regions of Europe), without any previous coronary history and with previous non conclusive exercise testing. When significant (> 50%) CS was suspected at MSCT, an angiocoronarography (AC) was done.RESULTSEighteen MSCT were normal, unsignificant CS (< 50%) were detected on 14 MSCT and significant coronary stenoses (SCS) for 13 P. Among this 13 P, 19 SCS were identified: 2 SCS of left main coronary artery (CA), 9 of the left descending CA, 6 of the right CA and 2 of the left circumflex CA. 13 CS were confirmed at AC. Finally, because of critical angiographic lesions +/- ischemia at nuclear tomoscintigraphy (NT), 9 P had coronary revascularization (7 catheter based, 2 surgical bypass), 4 P had medical treatment.DISCUSSIONBenefits of this preliminary study are obvious: 9 coronary revascularization/45 P. However, the place of MSCT for the screening of CS is uncertain, but may be usefull as a complement for the screening of coronary arterial disease.

Les auteurs presentent la premiere etude de depistage des lesions coronaires par le scanner multicoupes, dans une population de personnel navigant asymptomatique a risque cardiovasculaire absolu eleve. Les avantages et inconvenients respectifs de cet examen sont exposes, avant de discuter sa place dans l'algorithme diagnostique actuel.

In this paper we present the monitoring of an aerosol smog episode in urban area (Lyon, France). The maximum charge of aerosol in the atmosphere was about 2200T which find its origin principally in the traffic emission. A Lidar apparatus, network analyzers and numerical model were used to characterize the spatial and time distribution of the urban aerosol. By assuming an aerosol size distribution a quantitative map of the aerosol in the atmosphere Could be retrieved from the optical data. Comparison between Lidar data and PM10 standard analyzers had shown a relative good correlation near ground level. Air masses trajectories from ADMS model output and Lidar observation has been used to evaluated the local impact of the urban aerosols emission.

In this paper we present a novel approach using a genetic algorithm (GA) to solve the LIDAR "ill-problem". It is inverting aerosol size distribution from multi-wavelengths Lidar data in the UV-VIS-IR spectral range. This method do not need any predefined size distribution shape and is also running with data having poor S/N. Numerical convergence test of the GA have been done on both simulated data and on Lidar field measurements performed during the French POVA Campaign. It shows that size distribution is retrieved in millisecond rage, which represent a considerably decreasing in computing time consuming. Comparison between GA size distribution retrieval and SMPS ground-based measurements has been done showing an excellent agreement.

. Continuous mapping of an ozone episode in Paris in June 1999 has been performed using a differential absorption lidar system. The 2D ozone concentration vertical maps recorded over 33 h at the Champ de Mars are compiled in a video clip that gives access to local photochemical dynamics with unprecedented precision. The lidar data are compared over the whole period with point monitors located at 0-, 50-, and 300-m altitudes on the Eiffel Tower. Very good agreement is found when spatial resolution, acquisition time, and required concentration accuracy are optimized. Sensitivity to these parameters for successful intercomparison in urban areas is discussed.

Between January 1987 and December 1991, 68 consecutive patients aged 71.5 +/- 12.0 years underwent percutaneous implantation of a vena caval filter, mainly the LGM (N = 64). Fifty seven patients had pulmonary embolism, 61 had deep vein thrombosis of the lower limbs. The average follow-up interval was 4.9 +/- 3.3 years (7.0 +/- 2.7 years for the patients still alive). The follow-up included a telephonic enquiry to determine the date and cause of death, recurrent deep vein thrombosis and/or pulmonary embolism; surviving patients underwent clinical examination, plain abdominal X-ray with a lateral decubitus view and duplex ultrasonography of the lower limb veins to assess the patency of the filter. Fifty three per cent of the patients died. Four predictive factors for mortality were identified: a contra-indication to anticoagulant therapy, chronic post-embolic cor pulmonale, an indication of prophylactic implantation in the elderly and the presence of underlying malignant disease. There were 5.8% recurrences of pulmonary embolism, 26.1% of lower limb deep vein thrombosis and 25% of filter thrombosis. The only predictive factor of thrombosis was a proximal venous thrombus and was associated in 50% of filter thrombosis. Seventy per cent of the plain abdominal X-rays were abnormal with 9 displacements. 9 migrations and 10 closures of the filters. There was a significant correlation between closure on plain abdominal X-ray and caval thrombosis and between recurrent deep vein thrombosis and caval thrombosis. The frequency of long-term complications after implantation of a caval filter in this study suggests that interruption of the vena cava should be reserved for the only validated indications in the presence of a formal contra-indication to or failure of anticoagulant therapy. Other indications require evaluation with prospective randomised trials.

ROULEAU, F., et al. : Echocardiographic Assessment of the Interventricular Delay of Activation and Correlation to the QRS Width in Dilated Cardiomyopathy. The aim of the study was to define criteria for left ventricular pacing in dilated cardiomyopathy (DCM) using an echocardiographic evaluation of interventricular electromechanical delay (IMD) and a correlation of IMD to QRS duration. Standard 12‐lead ECG and echocardiography with pulsed Doppler tissue imaging (DTI) were recorded in 35 DCM patients ( mean age 58 ± 11 years ) with QRS duration from narrow (80 ms) to broad (222 ms) patterns. The time for left ventricular activation was evaluated from the onset of QRS to the onset of aortic flow (Q‐Ao) by standard pulsed Doppler (SP) or to the onset of mitral annulus systolic wave (Q‐Mit) (DTI). The time for right ventricular activation was determined from the onset of QRS to the onset of pulmonary flow (Q‐Pulm) (SP) or to the onset of tricuspid annulus systolic wave (Q‐Tri) (DTI). (Q‐Ao)–(Q‐Pulm) and (Q‐Mit)–(Q‐Tri) determined IMD for each method, respectively. QRS width and IMD showed correlation coefficients of r = 0.86 ([Q‐Ao]‐[Q‐Pulm]) and r = 0.82 ([Q‐Mit]‐[Q‐Tri]) ( P ≤ 0.001 ). Mean IMD of 77 ± 15 ms (SP) and 88 ± 26 ms (DTI) were noted for QRS width above 150 ms. Left ventricle delayed activation was positively correlated to QRS widening with both methods, ( r = 0.90, [Q‐Ao] ), ( r = 0.83, [Q‐Mit] ) ( P ≤ 0.001 ). In conclusion, QRS duration is a good marker of an interventricular mechanical asynchrony. According to IMD correction, left ventricular pacing may be mainly proposed to symptomatic DCM patients with QRS duration > 150 ms.

Analysis of the mechanism of action of estrogen receptor shows protein and mRNA polymorphism within distinct pituitary receptor-positive cells. The lactotropes exhibit unique properties in these mechanisms that distinguish them from gonadotropes. Therefore, this cell type constitutes an especially interesting model in the male as well as in the female for estrogen receptor studies.