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In the northeastern part of France, around the city of Metz, lichens (Hypogymnia physodes) have been transplanted from a single reference site to five different sites: (i) the reference site itself, (ii and iii) two peri-urban sites, (iv) a site in the proximity of a highway, and (v) a final one close to an industrial site. The dynamics of two different system set-ups (one covered and one uncovered) were evaluated. Samples have been collected 14, 34, and 68 days after transplantation. Lead concentrations already accumulated in the thallus, and the corresponding Pb isotopic compositions have been measured by quadrupole-based ICP-mass spectrometry. A systematic difference between the two setups is found for Pb concentrations, with the higher concentrations measured in lichens from the uncovered devices. Lead concentrations in lichens from the covered devices were found to be lower than or equal to the original concentration. Also the Pb isotopic compositions show a systematic difference between the devices, with the Pb isotopic composition present in lichens from the uncovered device being more radiogenic. Substantial changes in the isotopic composition of Pb are recorded for lichens from the uncovered device (from about 1.15 up to 1.22 for the 206Pb/207Pb ratio), in some cases already after only 34 days of exposure. The increases in the Pb concentration and the 206pb/207Pb ratio and the differences between the devices are explained by hypothesizing that (i) different Pb sources give rise to a different size distribution of aerosol particles and (ii) in the lichens present in the covered setup, a part of the aerosol particles cannot be incorporated. Also the influence of the source of the aerosols to lichens after transplantation is evaluated and the potential influence of biological reactions is discussed.

Background: It is currently thought that young adults are at increasing risk of exposure to deleterious sources of noise. To test this possibility we have assessed hearing status of young French men aged between 18 and 24 years in 1997 and study risk factors of deafness in a cross-sectional epidemiological study at selection centres for aptitudes to National Service., Methods: During the time of the study, 1208 subjects were examined. For each subject, data of an interview, an otoscopy and audiograms were collected. We compared hearing thresholds between subjects with different noise exposures and we determined risk factors of deafness in this population., Results: The prevalence of hearing loss was 9% at medium frequencies (0.5-2 kHz) and 15% at high frequencies (4-8 kHz).We found that 60% of the subjects were regularly exposed to at least one source of loud noise. Acoustic trauma (6%) mostly explained hearing losses. Repeated episodes of otitis media in childhood (17%) also emerged as an important risk factor apparently due to increased sensitivity to noise. In subjects with antecedent of otitis media, hearing impairments were significant in personal stereo users (>1 hour per day) (p<0.001), in those who went to discos and rock concerts (>2 times per month) (p=0.01) and in those who worked in noisy places (p=0.01). In contrast, in subjects without antecedent of otitis, we found no difference in hearing thresholds between noise exposed and non noise exposed subjects., Conclusions: Loud sound exposure is a true risk factor of early deafness in subjects that had had repeated episodes of otitis media in childhood. This study stresses the need for both prevention policies and information of health professionals and practitioners.

The main steps in the development of neuropsychology in France are briefly reviewed, from the early contribution of Paul Broca (1861) up until the early 1990s. The current epistemological and institutional crises is analyzed with respect to some general factors inherent to the domain (e.g., disputes between the proponents of the psychological and biological dimensions) and to particular factors related to the French situation (e.g., retirement of prominent neuropsychologists). As regards clinical practice and research activities, the future will probably show some fractionation of goals and techniques prior to new synthesis.

Prosopagnosia is an acquired neurological impairment characterized by an inability to experience a feeling of familiarity at the view of faces of known individuals and to identify these individuals. The inability of prosopagnosic patients to recognize faces does not entail that perceived faces go unprocessed in their brains, and there are indications that cognitive operations are still performed whereby a perceived face reactivates pertinent memories, but either these operations cannot be completed or their outcome fails to reach consciousness. A series of experiments were conducted on three severe prosopagnosic patients in an attempt to understand better this phenomenon known as covert face recognition, the conditions for its occurrence, and its functional locus. The capacity of the patients implicitly to access pertinent knowledge related to overtly unrecognized faces was inversely related to the severity of their perceptual deficit, suggesting that some preserved ability to extract the physiognomic invariants of a face is a necessary condition for the occurrence of the phenomenon. However, the results indicated that covert recognition does not take place at a perceptual or structural level although it is initiated at such a level, that it may have more than one underlying mechanism, and that it is achieved through the reactivation of specific information related to the individual's identity. Under special conditions that restricted the relevant knowledge that needed to be activated, transient overt recognition of faces was experienced by one of the prosopagnosic patients.