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Préparation et caractérisation de films polymériques biodégradables incorporant des extraits naturels à potentiel Antioxydante
(2026) BENDAHMANE Douaa; ALLAL Asma
This work focuses on the development of biodegradable polymeric films based on sodium alginate incorporating aqueous extract of Agave americana and silver nanoparticles (AgNPs) synthesized through a green method. AgNPs were synthesized using the plant extract and silver nitrate as a metallic precursor. Their formation was confirmed using several characterization techniques including UV-Visible spectroscopy, FT-IR, Zetasizer, and X-ray diffraction (XRD). The results demonstrated the formation of stable and crystalline silver nanoparticles. The prepared films exhibited good homogeneity, satisfactory flexibility, and physicochemical properties depending on the incorporated additives. The antioxidant activity evaluated by the DPPH assay showed a significant improvement in films containing plant extract and AgNPs. These findings highlight the potential of these biodegradable materials for applications in active packaging and biomedical fields.
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Évaluation de l’effet d’amendements organiques issus de sous-produits agroalimentaires sur la fertilité des sols et la croissance d’une culture test
(2026) Benzina nariman; Bentouir mama; Bourtal zerat Hanane; YAZIT SIDI-MOHAMMED
The valorization of agro-food by-products and their use as organic soil amendments represent a sustainable approach that contributes to improving soil fertility and reducing organic waste. In this context, this study aims to evaluate the effect of two types of organic amendments, namely eggshell and wheat bran, on some physicochemical properties of the soil as well as on the growth of a test crop of lettuce (Lactuca sativa L.). The experiment was conducted under controlled conditions using four treatments: control soil (T0), soil amended with eggshell (T1), wheat bran (T2), and a mixture of eggshell and wheat bran (T3). Several soil properties, including pH, electrical conductivity, and organic matter content, were analyzed before and after cultivation in addition to monitoring lettuce growth parameters. The results showed that the addition of organic amendments influenced soil properties and plant development. Eggshell application contributed to increasing soil pH and maintaining values close to neutrality due to its high calcium carbonate content, whereas wheat bran improved soil organic matter content and enhanced lettuce growth. The different treatments showed variations in soil and plant responses, highlighting the agronomic potential of these agro-food by-products as organic amendments. In conclusion, the use of eggshell and wheat bran as organic soil amendments represents a promising ecological and economic alternative for improving soil fertility and supporting plant production.
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Conception, modélisation et optimisation des antennes imprimées reconfigurable pour les systèmes de communication sans fil
(2026) HAMMOUTI Maroua; HACHMAOUI Abir; Ferouani Souheyla; MOHAMMED BELHADJ Khouloud
This thesis focuses on the study and design of a miniaturized and frequency-reconfigurable printed antenna. Using CST Studio Suite software, a patch-type structure was optimized through the introduction of slots and notches in order to reduce its dimensions while maintaining a fundamental resonant frequency of 2.4 GHz. The integration of PIN diodes as switching elements enables dynamic reconfiguration of the antenna across different frequency bands, particularly those used by Wi-Fi, LTE, and 5G standards. The obtained results highlight a compact, efficient, and adaptable solution that meets the growing requirements of modern telecommunication systems.
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Conception, modélisation et optimisation des antennes imprimées sélectives pour les systèmes de communication sans fil
(2026) BELHIA Nour El Houda; BOUKROLDA Hafssa; Ferouani Souheyla
This Master's Thesis presents the design and optimization of a selective and miniaturized printed antenna intended for 3G, 4G, and 5G mobile telecommunication networks. The work is based on the development of a rectangular patch antenna whose performance was enhanced through the introduction of slots and the integration of Defected Ground Structure (DGS) resonators in the ground plane. Electromagnetic simulations carried out using CST Microwave Studio validate a precise multiband operation at 1.83 GHz, 2.64 GHz, and 3.53 GHz. The proposed antenna exhibits good impedance matching, high isolation between the operating bands, and a miniaturization rate of 52.82%. The achieved gains are 2.34 dBi at 1.83 GHz (3G), 3.89 dBi at 2.64 GHz (4G), and 1.24 dBi at 3.53 GHz (5G). Owing to its compact size and filtering capabilities, the proposed antenna represents a promising solution for next- generation wireless communication systems
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Traitement des images médicales par Deep Learning : segmentation des polypes colorectaux pour l’aide au diagnostic
(2026) Bentsabet Seloua Amira; Boulefred Radouane; Belgrana Fatima Zohra
Colorectal cancer is one of the most pressing global public health challenges, with nearly 1.9 million new cases diagnosed annually. Colonoscopy remains the gold standard for its preven- tion; however, polyp miss rates ranging from 22% to 40% persist due to the high morphological variability of lesions and operator fatigue. This thesis presents CANet+ (Colorectal Attention Network Plus), an encoder-decoder Deep Learning architecture combining a ConvNeXt-Tiny en- coder, an Attention U-Net decoder, CBAM attention modules, an ASPP module for multi-scale context modeling, and a deep supervision mechanism.Evaluated on three standard benchmarks Kvasir-SEG, CVC-ClinicDB, and CVC-ColonDB using a four-fold cross-validation protocol, CANet+ achieves Dice scores between 0.92 and 0.96 and IoU values between 0.87 and 0.92, demonstrating competitive performance against methods. These results open concrete prospects for integrating Deep Learning based computer aided diagnosis and segmentation systems into real world clinical endoscopic practice.