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This study was conducted in the Ecole Normale Supérieure in Tetouan to detect the major difficulties that Moroccan students encounter in their learning of endocrinology and hormonal communication. To do this, we used semi-directive interviews to receive the opinions of these students in their learning of this subject. The final results of this survey have allowed us to identify the following difficulties according to the students: the inability to memorize the number of hormones, the complexity of the notions of endocrinology, the absence of material for practical work, the lack of supervised work sessions and the insufficiency of the time allocated to this subject. In conclusion, it turned out that the best way to help these students in their learning of endocrinology is to offer them a learning environment based on the diversified use of information and communication technologies. In other words, the well-thought-out use of tools such as digital animations could significantly increase the number of practical exercises to be performed.

Objectives The authors aimed to evaluate whether blood cadmium (B-Cd), lead (B-Pb) and mercury (B-Hg) in children differ regionally in 9 countries, and to identify factors correlating with exposure. Material and Methods The authors performed a cross-sectional study of children aged 7–14 years, living in 2007–2008 in urban, rural, or potentially polluted (“hot spot”) areas (ca. 50 children from each area, in total 1363 children) in 6 European and 3 non-European countries. The authors analyzed Cd, Pb, and total Hg in blood and collected information on potential determinants of exposure through questionnaires. Regional differences in exposure levels were assessed within each country. Results Children living near industrial “hot-spots” had B-Cd 1.6 (95% CI: 1.4–1.9) times higher in the Czech Republic and 2.1 (95% CI:1.6–2.8) times higher in Poland, as compared to urban children in the same countries (geometric means [GM]: 0.13 μg/l and 0.15 μg/l, respectively). Correspondingly, B-Pb in the “hot spot” areas was 1.8 (95% CI: 1.6–2.1) times higher than in urban areas in Slovakia and 2.3 (95% CI: 1.9–2.7) times higher in Poland (urban GM: 19.4 μg/l and 16.3 μg/l, respectively). In China and Morocco, rural children had significantly lower B-Pb than urban ones (urban GM: 64 μg/l and 71 μg/l, respectively), suggesting urban exposure from leaded petrol, water pipes and/or coal-burning. Hg “hot spot” areas in China had B-Hg 3.1 (95% CI: 2.7–3.5) times higher, and Ecuador 1.5 (95% CI: 1.2–1.9) times higher, as compared to urban areas (urban GM: 2.45 μg/l and 3.23 μg/l, respectively). Besides industrial exposure, traffic correlated with B-Cd; male sex, environmental tobacco smoke, and offal consumption with B-Pb; and fish consumption and amalgam fillings with B-Hg. However, these correlations could only marginally explain regional differences. Conclusions These mainly European results indicate that some children experience about doubled exposures to toxic elements just because of where they live. These exposures are unsafe, identifiable, and preventable and therefore call for preventive actions. Int J Occup Med Environ Health. 2023;36(3):349–64

Objectives: To describe blood lead (Pb-B), cadmium (Cd-B) and mercury (Hg-B) levels in children living in urban, industrial and rural areas in Fez city (north of Morocco) and to identify the determinants and some renal effects of exposure. Material and Methods: The study was conducted from June 2007 to January 2008 in 209 school children (113 girls, 96 boys), aged 6-12 years, from urban, industrial and rural areas in Fez city. Interview and questionnaires data were obtained. Blood and urinary samples were analyzed. Results: The mean of blood lead levels (Pb-B) in our population was 55.53 μg/l (range: 7.5-231.1 μg/l). Children from the urban area had higher blood lead levels (BLLs) mean (82.36 μg/l) than children from industrial and rural areas (48.23 and 35.99 μg/l, respectively); with no significant difference between boys and girls. BLLs were associated with traffic intensity, passive smoking and infancy in the urban area. The mean of blood cadmium levels (BCLs) was 0.22 μg/l (range: 0.06-0.68 μg/l), with no difference between various areas. Rural boys had higher BCLs mean than rural girls, but no gender influence was noticed in the other areas. BCLs were associated with the number of cigarettes smoked at children's homes. The blood mercury levels (BMLs) mean was 0.49 μg/l (range: 0.01-5.31 μg/l). The BMLs mean was higher in urban and industrial areas than in the rural area with no gender-related difference. BMLs were associated with amalgam fillings and infancy in the urban area. About 8% of the children had BLLs ≥ 100 μg/l particularly in the urban area, microalbuminuria and a decrease in height were noticed in girls from the inner city of Fez and that can be related to high BLLs (89.45 μg/l). Conclusions: There is a need to control and regulate potential sources of contamination by these trace elements in children; particularly for lead.

The Visual Evoked Potential (VEP) examination is used to analyze the appropriate functioning of the optical pathways from the retina to the visual cortex. In hospitals, the diagnosis made by physicians is based mainly on reading the temporal trace and identifying the latency P100. However, after a considerable research effort, it has been confirmed that this method is subjective and relatively less reliable. In our work, we report different approaches to resolve the inadequacy of traditional classification, by studying the efficiency of VEP signal classification in a comparative approach using 3 models: Model A: STFT-CNN, Model B: CWT-CNN, and Model C: Wigner-Ville-CNN, therefore we evaluate in the same context the effectiveness of using a pre-trained 2D CNN structure. The time-frequency transformation allows us to generate two-dimensional data from one-dimensional signals to bring out the integrated features that are not valued in the temporal plot, and then exploit them for good discrimination between the two classes, in order to be able to use a CNN-2D classification architecture, taking into consideration the advantages offered by this architecture in terms of the involvement of the attribute extraction phase and its efficiency in classifying 2D data. The results provided by the different scenarios proved that the Wigner-Ville transformation combined with a pre-trained CNN architecture can be considered a good method in terms of different performance metrics, which demonstrates that it is a successful candidate for providing significant assistance to physicians in their analysis of VEP signals.

The visual evoked potential as an electrophysiological signal is mainly used in the neurophysiological exploration of the optic nerves. Traditionally, medical doctors base their diagnosis of specific pathologies related to the time delay of the nerve flow on the time scale. In this context, the VEP latency P100 that reflects a temporal notion is considered the main characteristic on which human interpretation is based. However, its value is influenced by different factors and remains a limited method. This insufficiency triggers our interest instead in deep learning architectures, taking into consideration and adapting to the specificity of each particularity related to the laboratory of the neurophysiological exploration unit in the hospital. The comparison between the results obtained from Matlab by the application of the CNN as well as the RNN, based on the evaluation parameters calculated after k-fold cross-validation, confirms that the CNN-1D architecture can be considered powerful in terms of reliability of classification between signals that are related to pathological subjects and normal ones, which privileges the use of this architecture compared with recurrent neural networks that are less reliable and require more time for execution, subsequently the use of the CNN will allow us to avoid even the extraction of attributes for the discrimination between the two classes object of classification, with the possibility to progressively improve the performance of the solution over time based on the new signals acquired in the VEP analysis laboratory.