Le testament politique de Monzon. Texte bambara

Sauvageot Serge. Le testament politique de Monzon. Texte bambara. In: 2000 ans d’histoire africaine. Le sol, la parole et l’écrit. Mélanges en hommage à Raymond Mauny. Tome I. Paris : Société française d'histoire d'outre-mer, 1981. pp. 289-295. (Bibliothèque d'histoire d'outre-mer. Études, 5-6-1

Le testament politique de Monzon. Texte bambara

Sauvageot Serge. Le testament politique de Monzon. Texte bambara. In: 2000 ans d’histoire africaine. Le sol, la parole et l’écrit. Mélanges en hommage à Raymond Mauny. Tome I. Paris : Société française d'histoire d'outre-mer, 1981. pp. 289-295. (Bibliothèque d'histoire d'outre-mer. Études, 5-6-1

Hail detection using S and C band radar reflectivity difference

In reflectivity fields observed with conventional radar networks, hailstorm identification is not easy. In the present paper, a hailstorm detection method using two single-wavelength radars located far from each other is discussed. The two radars, C and S bands, respectively, are about 200 km apart. Because large hailstones are non-Rayleigh scatterers, the distribution of the dual-wavelength reflectivity ratio is shown to display an identifying signal for hail-bearing storms. The relevance and sensitivity of the proposed hail detection algorithm is first analyzed from a simulation of 10.7- and 5.3-cm radar observations. Various convective storm conditions, differing by the horizontal shape and the nature of precipitation, are considered, notably rain and hail with hailstones of different diameters, dry or coated with liquid water. The attenuation for the radar–target propagation path and inside the target is also taken into account. The dual-wavelength reflectivity ratio for all the simulated radar observations shows that the proposed criterion enables an identification of the hail-bearing storms. The algorithm is then applied to real cases of storms observed with the French meteorological radar network. The comparison of the hail areas identified by the dual-wavelength algorithm with the hail impacts observed with ground-based hailpad networks confirms the ability of the algorithm to detect the hail-bearing cells in proper time and place. It is concluded that the dual-wavelength reflectivity ratio has a potential for hail detection, using an operational radar network organized in such a way that the convective field can be simultaneously observed with both an S-band and a C-band radar

Hail detection using S and C band radar reflectivity difference

In reflectivity fields observed with conventional radar networks, hailstorm identification is not easy. In the present paper, a hailstorm detection method using two single-wavelength radars located far from each other is discussed. The two radars, C and S bands, respectively, are about 200 km apart. Because large hailstones are non-Rayleigh scatterers, the distribution of the dual-wavelength reflectivity ratio is shown to display an identifying signal for hail-bearing storms. The relevance and sensitivity of the proposed hail detection algorithm is first analyzed from a simulation of 10.7- and 5.3-cm radar observations. Various convective storm conditions, differing by the horizontal shape and the nature of precipitation, are considered, notably rain and hail with hailstones of different diameters, dry or coated with liquid water. The attenuation for the radar–target propagation path and inside the target is also taken into account. The dual-wavelength reflectivity ratio for all the simulated radar observations shows that the proposed criterion enables an identification of the hail-bearing storms. The algorithm is then applied to real cases of storms observed with the French meteorological radar network. The comparison of the hail areas identified by the dual-wavelength algorithm with the hail impacts observed with ground-based hailpad networks confirms the ability of the algorithm to detect the hail-bearing cells in proper time and place. It is concluded that the dual-wavelength reflectivity ratio has a potential for hail detection, using an operational radar network organized in such a way that the convective field can be simultaneously observed with both an S-band and a C-band radar

Evaluation of saliva as an alternative matrix for monitoring plasma Zidovudine, Lamivudine and nevirapine concentrations in Rwanda

Saliva may provide interesting advantages as matrix for compliance measurements, pharmacokinetic studies and therapeutic drug monitoring in resource limited countries. We investigated the feasibility of using saliva for compliance monitoring of zidovudine (ZDV), lamivudine (3TC) and nevirapine (NVP) in 29 HIV-1 infected patients from Rwanda. ZDV, 3TC and NVP drug levels were quantified by an LC/MS-MS method in plasma and stimulated saliva samples and compared using Bland-Altman analysis. Seven patients demonstrated undetectable saliva ZDV levels while five out of these seven also showed no 3TC salivary concentrations. For the other samples, we observed a good agreement between salivary and plasma concentrations of each antiretroviral drug. A significant relation between the difference in saliva and plasma ZDV concentrations and the average ZDV concentration in the two matrices was deduced as follow: y = -380.15 + 1.79 x. The log saliva and plasma concentration difference of both 3TC and NVP was consistent across the range of average log concentration. Overall, we showed large agreement limits suggesting a wide inter patient variability that may result to non-reliable plasma level predictions from saliva drug measurements. Therefore, our results indicate that saliva may serve as a valuable tool only for NVP compliance testing because of its high salivary concentration

cloud-to-ground lightning activity in hail-bearing convective storms.

The cloud-to-ground lightning flash (CG) produced by several apparent hailstorms are analyzed in different locations of southern Europe. The hail detection is performed via four different analysis techniques: radar reflectivity factor estimation, radar echo shape analysis, polarimetric hydrometeor identification, and reflectivity difference between radars with different wavelengths. The CG parameters considered are the flash rate and density, the flash polarity, the multiplicity, and the peak current. Some of the observed storms exhibit hail-bearing cell features, while others exhibit heavy precipitation rates without any apparent hail production. One of the hailstorms can be classified as severe because reported hailstorm diameters reach 39 mm. The CG lightning characteristics of both types of storms are compared. The CG rates corresponding to all hail-bearing storms are singularly lower than those of rain-only storms, typically by a factor 5. So, the CG rate of the hail-bearing storms considered does not exceed 2 min−1 while it can reach about 12 min−1 for heavy rain-bearing storms. Moreover, some of them can produce especially high positive CG proportions associated with negative CGs with low values of peak current and multiplicity. This last observation suggests that the negative charge available for CG flashes is weak within the cloud when positive CG flashes are dominant. In order to interpret the low CG rates observed in the case of hail-bearing storms several interpretations are discussed, but it would be necessary to know the intracloud flash activity in such cases of storms in order to enrich the discussion