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Introduction/purpose: Stainless steels have excellent corrosion resistance and adequate mechanical properties. However, their use in aggressively hydrogenated environments in the energy industry causes a loss of ductility. This work studied the effect of hydrogen on the mechanical behavior of the DINX15CrNiSi25.21/AISI310 austenitic stainless steel loaded in an aqueous solution of purely sulfuric acid H2SO4 at 1N at room temperature during tensile testing. Methods: Experimental characterization techniques are applied to standardised machining-manufactured tensile specimens which underwent a series of heat treatments ranging from quenching at 1050°C for 35 minutes to tempering at 680°C for 30 minutes. This is accompanied by a succession of immersions of these samples by cryogenic quenching cycles at -196°C for a duration of 1 hour. The hydrogen was electrolytically loaded in a Pyrex glass cell for various loading times, ranging from 1h00 to 15h00, with a step of 2h00. Results: The results showed a reduction in mechanical properties and plasticity. The electrochemical method confirmed the material's sensitivity to hydrogen embrittlement, calculating the embrittlement criterion EI (%). This method indicates a rapid increase in values depending on hydrogen loading times, with a maximum value of 41.60%. Conclusion: The study highlights the negative impact of hydrogen on the mechanical properties of AISI310 stainless steel, emphasising the need for reduced hydrogen exposure in steel applications.

The goal of this article is to provide a review of the experimental techniques and procedures using vibration methods for the Structural Health Monitoring (SHM) of Polymer-Matrix Composites (PMCs). It aims to be a guide for any researchers to carry out vibration experiments. The linear methods are first introduced. But, as PMC is a complex material, these classic methods show some limits, such as low accuracy for small damages and a high environmental dependency. This is why the nonlinear methods are secondly studied, considering that the complexity of PMCs induces a nonlinear behavior of the structure after damage occurrence. The different damage mechanisms are well-explained in order to evaluate the potential of each vibration method to detect them.

PurposeIn this study, we retrospectively reviewed the use of flow cytometry (FCM) in the diagnosis of inborn errors of immunity (IEIs) at a single center in Algeria. Sharing insights into our practical experience, we present FCM based diagnostic approaches adapted to different clinical scenarios.MethodsBetween May 2017 and February 2024, pediatric and adult patients presenting with clinical features suggestive of immunodeficiency were subjected to FCM evaluation, including lymphocyte subset analysis, detection of specific surface or intracellular proteins, and functional analysis of immune cells.ResultsOver a nearly seven-year period, our laboratory diagnosed a total of 670 patients (372 (55.5%) males and 298 (44.5%) females), distributed into 70 different IEIs belonging to 9 different categories of the International Union of Immunological Societies classification. FCM was used to diagnose and categorize IEI in 514 patients (76.7%). It provided direct diagnostic insights for IEIs such as severe combined immunodeficiency, Omenn syndrome, MHC class II deficiency, familial hemophagocytic lymphohistiocytosis, and CD55 deficiency. For certain IEIs, including hyper-IgE syndrome, STAT1-gain of function, autoimmune lymphoproliferative syndrome, and activated PI3K delta syndrome, FCM offered suggestive evidence, necessitating subsequent genetic testing for confirmation. Protein expression and functional assays played a crucial role in establishing definitive diagnoses for various disorders. To setup such diagnostic assays at high and reproducible quality, high level of expertise is required; in house reference values need to be determined and the parallel testing of healthy controls is highly recommended.ConclusionFlow cytometry has emerged as a highly valuable and cost-effective tool for diagnosing and studying most IEIs, particularly in low-income countries where access to genetic testing can be limited. FCM analysis could provide direct diagnostic insights for most common IEIs, offer clues to the underlying genetic defects, and/or aid in narrowing the list of putative genes to be analyzed.

ABSTRACT: Project-based learning is of great importance for German as a foreign language (DaF) instruction, as it allows learners to practice their language skills and intercultural competence in purposeful activities in a hands-on way. This article presents an innovative project for DaF instruction, in which DaF students from the German department of the University of Oran2 will translate and synchronize an episode of the Algerian series "Achour 10" into German. The challenge of taking on the roles of the characters in "Achour 10" and adapting the dialogues into German and then performing them synchronously is a challenge for students, but it is a practical way to promote individual competence development in a collaborative way. This oral presentation activity demonstrates the fluency and pronunciation of DaF students and encourages them to communicate cultural differences in a dialogue. This article describes the process of the different phases, as well as the strategies for implementing the project proposed by the teaching team. ZUSAMMENFASSUNG: Die Ausführung von Projektarbeiten ist für den DaF-Unterricht von einer großen Bedeutung, dadurch haben die Lernenden die Möglichkeit, ihre Sprachkenntnisse und ihre interkulturelle Kompetenz in zweckmäßigen Aktivitäten handlungsorientiert zu trainieren. In diesem Beitrag wird ein innovatives Projekt für den DaF-Unterricht vorgestellt, bei dem DaF-Studierende aus der Deutschabteilung der Universität Oran2 eine Folge der algerischen Serie „Achour 10“ ins Deutsche übersetzen und synchronisieren werden. Die Schwierigkeit die Rollen der Serie „Achour 10“ bzw. die Stimmen zu übernehmen und die ins Deutsche zu adaptieren und dann sie synchron zu spielen stellt in diesem Projekt eine Herausforderung für Studierenden aber eine praktische Weise die individuelle Kompetenzentwicklung in einer kollaborativen Weise zu fördern. Diese mündliche Präsentationsaktivität demonstriert die Geläufigkeit und Aussprache der DaF-Studierenden und fordert sie auf, kulturelle Besonderheiten in einem Dialog zu kommunizieren. Dieser Artikel beschreibt den Ablaufprozess der verschiedenen Phasen, sowie die Strategien zur Durchführung des Projekts, die vom Lehrerteam vorgeschlagen wurden.

Dieser Beitrag untersucht die Integration künstlicher Intelligenz (KI) in das Curriculum für Deutsch als Fremdsprache an der Universität Oran 2, mit dem Ziel, die Sprachkompetenz und technologische Bildung der Masterstudierenden zu fördern. Ausgehend von der algerischen ministeriellen Initiative zur Einbindung von KI im Bildungssektor evaluiert diese explorative Studie die Anwendung und pädagogische Wirksamkeit von KI-gestützten Lehrmethoden. Die Forschung verwendet ein exploratives Design, das eine Gruppendiskussion mit Studierenden umfasst, die KI-Tools für das Sprachenlernen nutzen, ergänzt durch eine Analyse der Kursstrukturen und Lehrmaterialien. Dieser Ansatz ermöglicht es, sowohl die unmittelbaren Auswirkungen auf den Lernprozess als auch die breiteren pädagogischen und ethischen Implikationen des Technologieeinsatzes tiefgehend zu verstehen. Die Ergebnisse liefern grundlegende Erkenntnisse für Empfehlungen zur Integration von KI in Sprachlehrpläne, um die Bildungserfahrung zu bereichern und die Studierenden effektiv auf die digitale Zukunft vorzubereiten. Abstract This paper examines the integration of Artificial Intelligence (AI) into the German as a Foreign Language curriculum at University Oran 2, with a focus on leveraging AI technologies to enhance language proficiency and technological literacy among master's students. Originating from Algeria's ministerial initiative to integrate AI in the educational sector, this explorative study assesses the application and educational effectiveness of AI-supported teaching approaches. The research utilizes an explorative design, incorporating a group discussion with students who use AI tools for language learning, complemented by an analysis of course structures and teaching materials. This explorative approach facilitates an in-depth understanding of both the immediate impacts on the learning process and the broader pedagogical and ethical implications of technology usage. The findings provide foundational insights for recommendations on embedding AI into language teaching curricula, aiming to enrich the educational experience and prepare students effectively for the digital future.

Introduction/purpose: Stainless steels have excellent corrosion resistance and adequate mechanical properties. However, their use in aggressively hydrogenated environments in the energy industry causes a loss of ductility. This work studied the effect of hydrogen on the mechanical behavior of the DINX15CrNiSi25.21/AISI310 austenitic stainless steel loaded in an aqueous solution of purely sulfuric acid H2SO4 at 1N at room temperature during tensile testing. Methods: Experimental characterization techniques are applied to standardised machining-manufactured tensile specimens which underwent a series of heat treatments ranging from quenching at 1050°C for 35 minutes to tempering at 680°C for 30 minutes. This is accompanied by a succession of immersions of these samples by cryogenic quenching cycles at -196°C for a duration of 1 hour. The hydrogen was electrolytically loaded in a Pyrex glass cell for various loading times, ranging from 1h00 to 15h00, with a step of 2h00. Results: The results showed a reduction in mechanical properties and plasticity. The electrochemical method confirmed the material's sensitivity to hydrogen embrittlement, calculating the embrittlement criterion EI (%). This method indicates a rapid increase in values depending on hydrogen loading times, with a maximum value of 41.60%. Conclusion: The study highlights the negative impact of hydrogen on the mechanical properties of AISI310 stainless steel, emphasising the need for reduced hydrogen exposure in steel applications. [ABSTRACT FROM AUTHOR]

Abstract Traditional laminated composites have fibres oriented only in the in-plane of the laminate due to their manufacturing process, and are therefore very susceptible to transverse cracking and delamination from out-of-plane actions. Delamination can considerably reduce the load bearing capacity of a structure hence several reinforcement solutions, based on the principle to add out-of-plane reinforcement to the 2D fabric, have been explored to enhance the delamination resistance. However, the usual textile technologies for Z-reinforcement such as weaving, knitting, stitching, z-pinning, and tufting generates perturbations that may alter the in-plane mechanical properties. Although tufting is a single needle and single thread based one side stitching (OSS) technique which can incorporate almost tension free through the thickness reinforcement in a material, various types of microstructural defects may be created during the manufacturing process and lead to a degradation of the in-plane properties of the composite. Moreover, due to awareness in environmental concerns, the development and use of eco-friendly biocomposites to replace synthetic ones has been increasing. This research work investigates the effect on in plane mechanical properties of adding through the thickness reinforcement (TTR) by tufting in a flax based composite laminate to improve the transversal strength. The glass fibre tufted laminates of 550 g/m2 flax fibre were moulded using a 38% biobased thermoset resin by vacuum bag resin transfer moulding (VBRTM). The tufted and un-tufted in-plane mechanical properties of green biocomposite were determined in tension, compression and shear in accordance with ASTM 3039, ASTM D7137 and EN ISO 14130, using universal INSTRON 1186 and MTS 20 M testing machines. The quantification of the in-plane mechanical properties established a reduction of the in plane tensile mechanical properties, due to tufting, whereas the reduction effects are marginal in compression. As expected, the glass fibre tufts strength the connection between core and skin of the composite so that the interlaminar shear strength, deduced from flexural tests with small span-to-thickness ratio, is increased. Thanks to Digital Image Correlation (DIC) performed during shear tests, an increase in interlaminar shear modulus is highlighted.

Nowadays, nonlinear vibration methods are increasingly used for the detection of damage mechanisms in polymer matrix composite (PMC) materials, which are anisotropic and heterogeneous. The originality of this study was the use of two nonlinear vibration methods to detect different types of damage within PMC through an in situ embedded polyvinylidene fluoride (PVDF) piezoelectric sensor. The two used methods are nonlinear resonance (NLR) and single frequency excitation (SFE). They were first tested on damage introduced during the manufacturing of the smart PMC plates, and second, on the damage that occurred after the manufacturing. The results show that both techniques are interesting, and probably a combination of them will be the best choice for SHM purposes. During the experimentation, an accelerometer was used, in order to validate the effectiveness of the integrated PVDF sensor.

Purpose: In this study, we retrospectively reviewed the use of flow cytometry (FCM) in the diagnosis of inborn errors of immunity (IEIs) at a single center in Algeria. Sharing insights into our practical experience, we present FCM based diagnostic approaches adapted to different clinical scenarios. Methods: Between May 2017 and February 2024, pediatric and adult patients presenting with clinical features suggestive of immunodeficiency were subjected to FCM evaluation, including lymphocyte subset analysis, detection of specific surface or intracellular proteins, and functional analysis of immune cells. Results: Over a nearly seven-year period, our laboratory diagnosed a total of 670 patients (372 (55.5%) males and 298 (44.5%) females), distributed into 70 different IEIs belonging to 9 different categories of the International Union of Immunological Societies classification. FCM was used to diagnose and categorize IEI in 514 patients (76.7%). It provided direct diagnostic insights for IEIs such as severe combined immunodeficiency, Omenn syndrome, MHC class II deficiency, familial hemophagocytic lymphohistiocytosis, and CD55 deficiency. For certain IEIs, including hyper-IgE syndrome, STAT1-gain of function, autoimmune lymphoproliferative syndrome, and activated PI3K delta syndrome, FCM offered suggestive evidence, necessitating subsequent genetic testing for confirmation. Protein expression and functional assays played a crucial role in establishing definitive diagnoses for various disorders. To setup such diagnostic assays at high and reproducible quality, high level of expertise is required; in house reference values need to be determined and the parallel testing of healthy controls is highly recommended. Conclusion: Flow cytometry has emerged as a highly valuable and cost-effective tool for diagnosing and studying most IEIs, particularly in low-income countries where access to genetic testing can be limited. FCM analysis could provide direct diagnostic insights for most common IEIs, offer clues to the underlying genetic defects, and/or aid in narrowing the list of putative genes to be analyzed. [ABSTRACT FROM AUTHOR]

This paper reports a study of bioclimatic dynamics and land use in the region of Tlemcen (north-west of Algeria). GIS (geographic information system) and satellite images (LandSat) were used to conduct a diachronic study based on a series of satellite images from the years 2000 and 2019 to demonstrate changes in the study area while highlighting the importance of environmental conditions, including climate and anthropogenic impact on dynamic vegetation cover. Bioclimatic synthesis has shown an improvement in the rainfall regime and an evolution towards higher bioclimatic atmospheres between the two periods (1985–1999) and (2004–2018). Land use in the study area is under the influence of strong anthropogenic pressures and is experiencing a decline in forest areas from 28.74 to 17.49% but also in agricultural land and lawns from 38.61% to 27.67% in favour of built-up areas which increased from 0.81% to 1.09% but mainly to the benefit of bare soil: an ultimate stage of degradation whose surface area increased from 31.59% in 2000 to 53.46% in 2019. [ABSTRACT FROM AUTHOR]

BackgroundInborn errors of immunity (IEI) predispose patients to various infectious and non-infectious complications. Thanks to the development and expanding use of flow cytometry and increased awareness, the diagnostic rate of IEI has markedly increased in Algeria the last decade.AimThis study aimed to describe a large cohort of Algerian patients with probable IEI and to determine their clinical characteristics and outcomes.MethodsWe collected and analyzed retrospectively the demographic data, clinical manifestations, immunologic, genetic data, and outcome of Algerian IEI patients - diagnosed in the department of medical immunology of Beni Messous university hospital center, Algiers, from 2008 to 2021.ResultsEight hundred and seven patients with IEI (482 males and 325 females) were enrolled, 9.7% of whom were adults. Consanguinity was reported in 50.3% of the cases and a positive family history in 32.34%. The medium age at disease onset was 8 months and at diagnosis was 36 months. The median delay in diagnosis was 16 months. Combined immunodeficiencies were the most frequent (33.8%), followed by antibody deficiencies (24.5%) and well-defined syndromes with immunodeficiency (24%). Among 287 patients tested for genetic disorders, 129 patients carried pathogenic mutations; 102 having biallelic variants mostly in a homozygous state (autosomal recessive disorders). The highest mortality rate was observed in patients with combined immunodeficiency (70.1%), especially in patients with severe combined immunodeficiency (SCID), Omenn syndrome, or Major Histocompatibility Complex (MHC) class II deficiency.ConclusionThe spectrum of IEI in Algeria is similar to that seen in most countries of the Middle East and North Africa (MENA) region, notably regarding the frequency of autosomal recessive and/or combined immunodeficiencies.

This article investigates the interest of using in-situ piezoelectric (PZT and PVDF) disks to perform real-time Structural Health Monitoring (SHM) of glass fiber-reinforced polymer composites submitted to various tensile loadings. The goal is to evaluate the working range and SHM potential of such embedded transducers for relatively simple mechanical loadings, with the long-term aim of using them to monitor complete 3D structures submitted to more complex loadings. SHM is performed acquiring the electrical capacitance variation of the embedded transducers. To study the potential links between the in-situ capacitance signal and the global response of the loaded host specimens, a multi-instrumentation composed of external Nondestructive Testing techniques was implemented on the surfaces of the specimens to search for multi-physical couplings between these external measurements and the capacitance curves. Results confirmed the non-intrusiveness of the embedded transducers, and allowed estimating their working domain. PZT capacitance signal follows well the mechanical loadings, but the piezoceramic transducer gets damaged after a determined relatively low strain level due to its brittleness. The limits of this working domain are extended by using a stretchable PolyVinylidene Fluoride (PVDF) polymer transducer, allowing this one to perform in-situ and real-time SHM of its host tensile specimens until failure.