Carcinome papillaire intra kystique du sein chez l’homme : à propos d’un cas

Intra cystic papillary carcinoma (IPC) of the breast is a very rare entity. In this observation we report the case of an IPC in an 89-year-old patient, who presented with cystic swelling of the right breast, classified as Bi-rads 4, a total mastectomy without axillary dissection was performed, the diagnosis of an IPC was confirmed by anatomopathological and immunohistochemical studies. IPC is not a common form of breast cancer in men, its prognosis is good even in the absence of axillary dissection and adjuvant therapy.Le carcinome papillaire intra kystique (CPIK) du sein est une entité très rare. Dans cette observation nous rapportons le cas d’un CPIK chez un patient âgé de 89 ans, qui présentait une tuméfaction kystique du sein droit, classée Bi-rads 4, une mastectomie totale sans curage axillaire a été réalisée, le diagnostic d’un CPIK a été confirmé par les études anatomopathologique et immunohistochimiques. Le CPIK n’est pas une forme habituelle du cancer du sein chez l’homme, son pronostic est bon même en absence de curage axillaire et de traitement adjuvan

Amelioration of mechanical and rheological characteristics of a ceramic Slip by adding of bentonite

This work is a contribution to the amelioration of the mechanical and rheological properties of a slip of ceramic used in the ceramic fabrication process. A study of characterization of slip of ceramic modified by bentonite has been accomplished chemically, physically, mechanically and rheologically. Chemical analysis showed that the slip modified by bentonite consist essentially of silica with a ratio (SiO_2/Al_2 O_3) average equal to 3.5 and the ratio of clays (Al2O3/SiO2) is relatively stable with increasing percentage of bentonite in the slip, with an average 0.28. The mechanical and rheological tests showing that increasing the percentage of bentonite in base slip caused an increase in the mechanical resistance, the yield stress and rapid decrease in density of the slip

Bioremediation of hexavalent chromium by an indigenous bacterium Bacillus cereus S10C1: optimization study using two level full factorial experimental design

The present study is focussed on chromium removal by indigenous chromium-resistant microorganisms isolated from soil and sludge samples of an industrial site. The optimal bioremediation conditions, namely temperature, hexavalent chromium (Cr(VI)) initial concentration, pH and time were determined by using a full factorial design at two levels. The results showed that from the 54 bacterial strains, S10C1 identified as Bacillus cereus 4080 LBK (NCBI:txid1396) was the most efficient strain in removing Cr(VI). The analysis of variance (ANOVA) results indicated that pH, Cr(VI) initial concentration, time and the interaction terms (T°–pH), (T°–time) and (Cr(VI) initial concentration–pH), have a significant influence on Cr(VI) removal yield. Moreover, the prescribed first-order regression model fitted well to the experimental data with a high coefficient of determination ($R^{2} = 0.969$). According to the response optimizer of Design-Expert software, the optimum conditions for chromium biodegradation were: a pH of 3, a temperature of 55 °C, a Cr(VI) initial concentration of 0.5 mM and a contact time of 20 hours. Under these conditions the experimental Cr(VI) removal percentage was found to be about 92.9% which is close to the predicted value by the statistical design (94.4%)

A contribution to security management in the Internet of things : RPL routing protocol

L’Internet des objets (IoT) est un nouveau paradigme de réseaux qui fournit des connexions intelligentes entre différents objets de besoins quotidiens. Cependant, ces connexions sont caractérisées par diverses contraintes, telles qu’un taux de perte élevé et un faible débit. Afin d’assurer ces connexions, il est nécessaire d’utiliser des protocoles de routage adaptés à ces contraintes. Dans la couche réseau, le protocole de routage RPL (de l’acronyme anglais IPv6 Routing Protocol for Low-power and Lossy Network) qui a été normalisé en 2012 par l’IETF (Internet Engineering Task Force), est considéré comme l’un des protocoles les plus utilisés dans le déploiement de ce type de réseau. Cependant, malgré ses avantages éminents et les différentes solutions de sécurité proposées dans la littérature, le protocole RPL souffre encore de nombreuses vulnérabilités qui conduisent à diverses menaces de sécurité. Dans cette thèse, nous nous intéressons à l’aspect sécuritaire du protocole RPL, en particulier l’attaque contre le rang. Tout d’abord, nous présenterons un état de l’art approfondi de l’attaque contre la valeur de rang dans les topologies RPL, avec une comparaison de plusieurs attaques à l’aide du test statistique de Friedman. Ensuite, nous présenterons une nouvelle attaque appelée DCB-Attack qui vise à concrétiser une faille de sécurité dans le processus de choix des parents préférés. L’idée principale de l’attaque est de diviser la topologie du réseau par plusieurs manipulations des valeurs de rang. Ensuite, le nœud malveillant choisit le pire parent pour diffuser le trafic vers le nœud racine. Dans RPL, la valeur du rang représente la position relative de chaque nœud par rapport au nœud racine, elle est calculée à l’aide d’une fonction objective. À cet égard, nous avons utilisé cette propriété pour fournir un schéma de sécurité efficace qui permet une sélection sécurisée des parents préférés dans les topologies RPL, et donc, détecter les comportements malveillants causés par la DCB-Attack. Ce schéma d’atténuation permet aux nœuds de calculer deux seuils de confiance (ThRankmin et ThRankmax) en fonction des valeurs des rangs des nœuds voisins. En appliquant l’algorithme proposé, chaque nœud serait en mesure de juger si un nœud est malveillant ou non, en vérifiant sa valeur de rang avec les deux seuils de confiance et le comportement malveillant de l’attaque et l’efficacité du schéma proposé ont été évalués à travers des simulations détaillées à l’aide du simulateur Contiki/Cooja. Les résultats des évaluations et du test statistique présentés dans cette thèse, montrent une bonne efficacité de notre schéma, en termes de taux de détection, de nombre moyen de sauts dans le réseau et de consommation globale d’énergie.The Internet of Things (IoT) is a new networking paradigm that provides intelligent connections between different objects of everyday life. However, these connections are characterized by various constraints, such as high loss rate and low throughput. In order to provide these connections, it is necessary to use routing protocols adapted to these constraints. At the network layer, the RPL routing protocol (IPv6 Routing Protocol for Low-power and Lossy Network) which was standardized in 2012 by the IETF, is considered one of the most widely used protocols in the deployment of such networks. However, despite its eminent advantages and the various security solutions proposed in the literature, the RPL protocol still suffers from many vulnerabilities that lead to various security threats. In this thesis, we focus on the security aspects of the RPL protocol, in particular the attack against the rank property. First, we will present a thorough state-of-the-art of the rank attacks in RPL topologies, with a comparison of several attacks using the Friedman statistical test. Then, we will propose a new attack called DCB-Attack that aims to concretize vulnerability in the preferred parents selection process. The main idea of this attack is to split the network topology by several manipulations of the rank values. Then, the malicious node chooses the worst parent to forward the traffic to the root. In RPL, the rank value represents the relative position of each node compared to the root node it is calculated using an objective function. In this regard, we used this property to provide an effective security scheme that allows secure selection of preferred parents in RPL, in order to detect the malicious behavior caused by DCB-Attack. This mitigation scheme allows nodes to calculate two trust thresholds (ThRankmin and ThRankmax) based on the rank values of neighboring nodes. By applying the proposed algorithm, each node would be able to judge whether a node is malicious or not, by checking the rank of this later node with both thresholds (ThRankmin and ThRankmax). The malicious behavior of the attack and the effectiveness of the proposed scheme were evaluated through detailed simulations using the Cooja simulator. The results of these evaluations and the statistical tests presented in this thesis, show a good effectiveness of our scheme in terms of attack-detection rate, average network hops and the global energy consumption

English as a foreign language teachers’ perspectives on new curriculum reform at Algerian middle schools: English as a foreign language teachers’ perspectives

This study investigates teachers' perspectives on EFL curriculum reform in Algeria. The specific objectives of the inquiry are to examine teachers' views about EFL curriculum reform relevance and procedures and draw a conclusion from their perspectives. 176 EFL teachers from middle schools in Algeria were chosen to serve as respondents in this research. The requisite data were collected through a survey and a semi-structured interview. The SPSS (22) programme was used to analyse quantitative data, whereas content analysis was subjected to qualitative data. The study established that the majority of teachers considered reform as not relevant to them. The findings also showed negative perspectives about procedures undertook by the government. Hence, we concluded that Algerian teachers' views about the new EFL reform are not in the same boat with the government's intentions and actions. This study, therefore, recommends that effort be made by the government and other agents to re-look to the reform and teachers' needs and motivation

Conciencia Emocional y participación en los estudiantes del Primer Curso de Español en la Universidad Amar Télidji de Laghouat

El objetivo de este trabajo es estudiar la relación entre la conciencia emocional y la participación en los estudiantes del primer curso del Departamento de Español, en la Universidad de Laghouat. La muestra refleja a todos los alumnos que estudian en el primer curso de español, utilizando la observación no participante y el cuestionario TMMS-24 como técnicas y herramientas para recolectar datos, con el propósito de determinar la relación entre la conciencia emocional de los estudiantes y su participación en el aula de ELE siguiendo un enfoque mixto. Los resultados obtenidos revelan una atención emocional superior en los estudiantes de sexo masculino en comparación con los de sexo femenino. En este contexto y por último, se confirma la relevancia entre la conciencia emocional y la participación en los estudiantes del primer curso

Would ChatGPT-facilitated programming mode impact college students’ programming behaviors, performances, and perceptions? An empirical study

Abstract ChatGPT, an AI-based chatbot with automatic code generation abilities, has shown its promise in improving the quality of programming education by providing learners with opportunities to better understand the principles of programming. However, limited empirical studies have explored the impact of ChatGPT on learners’ programming processes. This study employed a quasi-experimental design to explore the possible impact of ChatGPT-facilitated programming mode on college students’ programming behaviors, performances, and perceptions. 82 college students were randomly divided into two classes. One class employed ChatGPT-facilitated programming (CFP) practice and the other class utilized self-directed programming (SDP) mode. Mixed methods were utilized to collect multidimensional data. Data analysis uncovered some intriguing results. Firstly, students in the CFP mode had more frequent behaviors of debugging and receiving error messages, as well as pasting console messages on the website and reading feedback. At the same time, students in the CFP mode had more frequent behaviors of copying and pasting codes from ChatGPT and debugging, as well as pasting codes to ChatGPT and reading feedback from ChatGPT. Secondly, CFP practice would improve college students’ programming performance, while the results indicated that there was no statistically significant difference between the students in CFP mode and the SDP mode. Thirdly, student interviews revealed three highly concerned themes from students' user experience about ChatGPT: the services offered by ChatGPT, the stages of ChatGPT usage, and experience with ChatGPT. Finally, college students’ perceptions toward ChatGPT significantly changed after CFP practice, including its perceived usefulness, perceived ease of use, and intention to use. Based on these findings, the study proposes implications for future instructional design and the development of AI-powered tools like ChatGPT

A Clustering algorithm for distributing certificates in OLSR protocol

International audienceMobile Ad hoc Networks (MANET) define a novel architecture of wireless networks, where pre-established infrastructures are not necessary to communicate. Their mobile nodes are mainly designed to cooperate in order to manage their communications. However, security can be a crucial issue due to the absence of the infrastructure, which is often considered as a defence layer against cyber-attacks. In this paper, an improved model to distribute certificates in MANETs is proposed. Our work is based on optimized link state routing protocol (OLSR), where a novel yet-simple mechanism for forming clusters is introduced. The primary results of the proposal tend to be promising in terms of efficiency compared to some state-of-the art algorithms

Divide and Conquer-based Attack against RPL Routing Protocol

International audienceThe Internet of Things (IoT) is a new paradigm of networks that offers intelligent connections between different objects of daily basis needs. These connections are clearly characterized by various constraints, such as the high loss rate and the low throughput. To ensure these connections, it is necessary to use routing protocols adapted to these constraints. The routing protocol for low power and lossy networks (RPL) is one of the famous protocols used in this category of networks, thanks to its flexibility and adaptability. In this paper, the study attempts to present the deficiency of the RPL protocol against a new attack called divide and conquer-based attack. The idea is to introduce a malicious node periodically launching a process based on the rank value, in order to deteriorate the network performance. The attack effectiveness is investigated through a detailed simulation using the Cooja simulator in terms of the total number of victim nodes, the average network hops and the global energy consumption