Quality evaluation and biological properties of Algerian commercial honeys labeled as Rosemary, Tamarisk, Thistle and multiflora

Mestrado de dupla diplomação com a Université Moulay TaherHoney is considered a natural sweet substance produced by honeybees, from the nectars of plant flowers and honeydews. Honey has always been regarded as a food that is beneficial for human health with several therapeutic qualities described. The quality of honey is still a top concern for experts as no good method has been defined so far for the simultaneous detection of different types of honey. Consequently, the development of easy, quick, precise analytical tools that may give data for assessing honey authenticity, is important. Because of that, it is essential to inform consumers of the mislabeling of honey with lower quality. This study aimed to evaluate the physicochemical characteristics and to assess the quality of Algerian honey from different botanical and geographical origins. For that, ten samples of honey with different marked botanical origins were analyzed, including three samples from rosemary honey, three from tamarisk honey, three from milk thistle honey and one multiflora honey. The quality of the samples was determined through different parameters. Melissopalynological and physicochemical analyses (color, moisture, pH, acidity, electrical conductivity, diastase index, proline, 5-hydroxymethylfurfural, mineral content, proteins, carbohydrates, energy, and ash) were performed, as well as the profile evaluation of sugar and phenolic compounds. Antioxidant activity (reducing power and DPPH free radical scavenging activity) antitumor and anti-inflammation activity were also evaluated. Finally, the presence of antibiotics, recurrent residues in honey, such as tetracyclines and sulphonamides were screened using the multi-analyte receptor assay system Charm II. The melissopalinological analysis showed the presence of 10 major types of pollen grains, with Rosmarinus officinalis, Cytisus stratitus and Centaurea sp. pollens as the most abundant. Furthermore, since no honeydew elements were detected, all the samples were classified as nectar honeys. Samples R1, R2, and R3 were classified as rosemary monofloral honey; samples T1, T2 and MF were classified as Cytisus striatus honey; CH1-CH3 were classified as Centaurea sp. and T3 as multifloral, which not always agreed with the labeled botanical origin. Generally, honey samples presented values of moisture, free acidity, 5-HMF, proline content, and diastase index within the limits of the legal requirements, suggesting that the honey was extracted at a correct ripeness stage. The results showed that almost all honey samples have light amber color, except the rosemary honeys which presented an extra white amber color. Although exhibiting a normal diastase index, the R2 and R3 samples presented a 5-HMF value higher than the admitted in the legislation, suggesting that less adequate heat treatments and/or conservation methods might have been employed. The most common minerals were potassium, sodium, calcium, manganese, while copper and Manganese were present in some samples in minor quantities and the heavy metals (cadmium and lead) are absent from all samples. The sugar profile, analyzed by high pressure liquid chromatography with refractive index detection (HPLC-RI), showed that fructose and glucose were the most abundant compounds, representing more than 60% of total sugars. Other sugars, such as turanose, maltulose and maltose were also detected in a lower proportion. Regarding the phenolic profile, nineteen compounds (eight phenolic acids and seven flavonoids), two isoprenoid compounds (trans, trans- and cis, trans- abscisic acid), one spermidine and one phenolic diterpene were identified. T2 sample showed a higher amount of phenolic acids than flavonoids. However, the most abundant compounds were the benzoic acid derivative which was detected in all samples. Concerning the evaluation of the antitumor activity and anti-inflammatory activity the samples showed a significant potential. Finally, concerning the antibiotics screening, not all the samples showed negative results.O mel é considerado uma substância doce natural produzida pelas abelhas, a partir dos néctares das flores das plantas e de meladas. O mel sempre foi considerado um alimento benéfico para a saúde, com várias qualidades terapêuticas descritas. A sua qualidade ainda é uma das principais preocupações para os especialistas, pois não há um método ideal para a classificação simultânea de diferentes tipos de mel. Consequentemente, é importante o desenvolvimento de ferramentas analíticas simples, rápidas e precisas que possam fornecer dados que permitam avaliar a autenticidade do mel. Por esse motivo, é essencial informar os consumidores da incorreta rotulagem de méis com baixa qualidade. O objetivo deste estudo foi avaliar as características físico-químicas e desse modo aferir a qualidade de méis argelinos com diferentes origens botânicas e geográficas. Para isso, foram recolhidas dez amostras de méis rotulados com diferentes origens botânicas, nomeadamente: três de mel de alecrim, três de mel de tamarino, três de mel de cardo e um de mel multifloral. A qualidade dos méis foi aferida através de diferentes parâmetros. Foram realizadas análises melissopalinológicas e físico-químicas (cor, humidade, pH, acidez, condutividade elétrica, índice diastático, prolina, 5-hidroximetilfurfural, conteúdo em minerais, proteínas, hidratos de carbono, energia e cinzas), bem como a avaliação do perfil em açúcares e compostos fenólicos. Também foi avaliada a atividade antioxidante (poder redutor e poder bloqueador de radicais livres) e atividade antitumoral e antiinflamatório. Finalmente, a presença de antibióticos, resíduos recorrentes no mel, como tetraciclinas e sulfonamidas, foram investigados através do sistema de despistagem Charm II. A análise melissopalinológica mostrou a presença de 10 tipos de grãos de pólen maioritários, sendo os pólenes de Rosmarinus officinalis, Cytisus stratitus e Centaurea sp. os mais abundantes. Além disso, e como não foram detetados elementos de melada, as amostras analisadas foram classificadas como méis de néctar: as amostras R1, R2 e R3 foram classificadas como mel monofloral de alecrim; as amostras T1, T2 e MF foram classificadas como mel de Cytisus striatus; CH1-CH3 foram classificados como de Centaurea sp. e T3 como multifloral, nem sempre coincidindo com a classificação utilizada no rótulo. De uma forma geral, as amostras de mel apresentaram valores de humidade, acidez livre, 5-HMF, teor de prolina e índice de diástase dentro dos limites requeridos legalmente, sugerindo que os méis foram extraídos no nível de maturação correto. Os resultados mostram que quase todas as amostras de mel apresentaram uma color âmbar clara, exceto o mel de alecrim que apresentou uma color âmbar extra clara. Apesar de apresentarem um índice de diástase normal, as amostras R2 e R3 apresentaram um valor de 5-HMF superior ao admitido na legislação, sugerindo a utilização de tratamentos térmicos e/ou métodos de conservação menos adequados. Os minerais mais comuns identificados foram o potássio, sódio, cálcio, enquanto cobre e manganês estiveram presentes em algumas amostras em quantidades menores e os metais pesados (cádmio e chumbo) estão ausentes em todas as amostras. O perfil dos açúcares, analisado por cromatografia líquida de alta pressão com deteção de índice de refração (HPLC-RI), mostrou que a frutose e a glucose foram os compostos mais abundantes, representando mais de 60% dos açúcares totais. Outros açúcares, como a turanose, a maltulose e a maltose, também foram detetados em menor proporção. Em relação ao perfil fenólico, foram identificados dezanove compostos (oito ácidos fenólicos e sete flavonóides), dois compostos isoprenóides (ácido trans, trans- e cis, trans-abscísico), uma espermidina e um diterpeno fenólico. No que diz respeito à avaliação da atividade antitumoral e atividade anti-inflamatória, as amostras apresentam potencial significativo. Finalmente, após o estudo de deteção de antibióticos verificou-se que nem todas as amostras estão isentas de resíduos

Conception de systèmes multi-antennes multi-bandes pour terminaux mobiles LTE

Multiple antennas techniques are an interesting solution to increase throughput without increasing the bandwidth. This is an advantage in a context where the proliferation of users and services leads to a saturation of spectrum. However, the systems based on diversity raise new challenges for their integration into terminals. The work presented in this thesis is to consider jointly the performance of multi-antennas systems and integration into terminals constraints. Developed systems operate in two bands LTE: 790-862 MHz and 2.5-2.69 GHz, and cover also for some of them the upper part of the band TVWS (TVWhite Space): 700-790 MHz to provide cognitive radio applications. The first study is concentrated on designing an efficient system while maintaining a reasonable size. The proposed system is integrated into the terminals emerging in the market today such as mini-tablets, the tablet-phone hybrid or laptop. Very satisfactory performance in terms of bands and isolation are achieved. Aiming the size reduction, we propose an alternative compact system providing acceptable performances. For this purpose, three prototypes are proposed where the last could be integrated into a mobile phone. For all systems, we have evaluated the diversity performances in terms of correlation coefficient and Mean Effective Gain. It has been founded that the systems provide good diversity performances even if the terminal's position is changed during the communication. Moreover, the influence on the antennas performances with a presence of users is studied. The results show that these systems are suitable for LTE and can be used for MIMO wireless communications.Les techniques à base d’antennes multiples constituent une solution intéressante à l’augmentation du débit sans accroître la bande passante. Cependant, la conception de systèmes à base de diversité soulève de nouveaux défis quant à leur intégration au sein de terminaux à encombrement réduit. Le travail présenté consiste à prendre en compte conjointement les éléments déterminant les performances de communication multi-antennes et les contraintes d’intégration liées aux terminaux. Les systèmes développés fonctionnent dans deux bandes LTE: 790-862 MHz et 2.5-2.69 GHz; certains couvrent également la partie haute de la bande TVWS (TV White Space): 700-790 MHz afin d’offrir des applications de radio cognitive. Pour la première conception, la démarche consiste à obtenir un système performant sans rechercher, dans un premier temps une forte intégration. Néanmoins, le système proposé est intégrable dans des terminaux émergeant dans le marché actuel comme l’hybride téléphone-tablette. Des performances très satisfaisantes en termes de bandes et d’isolation sont atteintes. Ensuite, on privilégie la compacité du système tout en offrant des performances acceptables. Cette démarche permet la conception de trois prototypes, dont le dernier est intégrable dans un téléphone.D’autre part, l’influence de la présence d’un utilisateur mais également de l’intégration dans un terminal multimédia sur les performances des systèmes est étudiée. Enfin, les performances en diversité sont évaluées dans différentes configurations d’environnements. Les résultats ont montré que ces systèmes sont adaptés à la technologie LTE et offrent la possibilité d’établir des communications sans fil MIMO

Etude de la symbiose à rhizobia chez la fève (Vicia faba L.) et la luzerne (Medicago sativa L.) cultivée sous contrainte hydrique : aspects morpho-physiologiques et agronomiques

Le déficit hydrique affecte considérablement la croissance des plantes : c’est, sans doute, l’un des facteurs majeurs qui limite la production végétale en conditions naturelles. Dans ce travail, l’effet du stress hydrique sur la croissance et la symbiose à rhizobia, a été étudié chez cinq variétés et populations de Vicia faba L. et de Medicago sativa L. L'objectif de cette thèse est de mettre en évidence, les réponses au déficit hydrique chez la fève et la luzerne, en vue d'identifier des critères pour la sélection au sein de ces variétés et populations, celles les mieux adaptées à la sécheresse. Les mécanismes étudiés ont porté principalement sur des aspects morphologiques, physiologiques, biochimiques et symbiotiques. L’effet du stress hydrique se traduit par un effet dépressif sur tous les paramètres de croissance (hauteur des plants, surface foliaire, ainsi que le poids sec), de la nodulation et de la fixation symbiotique d’azote (nombre des nodules/plant, poids sec des nodules et teneurs en leghémoglobine), les pigments chlorophylliens et les caroténoïdes sont également réduits. Une augmentation des teneurs en proline et en sucres solubles chez toutes les variétés et les populations est enregistrée. Cet effet varie en fonction des traitements hydriques, de la variété et de la population. Les résultats obtenus montrent que la population Doucen et la variété Luz de otono chez la fève, Diamant et Baldia chez la luzerne, montrent une tolérance au stress hydrique, contrairement aux variétés Moapa et Dista chez la luzerne, Manouth et Tolga chez la fève qui se sont avérées sensibles aux conditions de déficit hydrique. Cette étude pourrait servir à la définition de critères pertinents de la résistance à la sécheresse utilisables en sélection variétale. La variété Luz de otono et la population Doucen chez la fève, Diamant et Baldia chez la luzerne présentent des teneurs relatives en eau et en pigments chlorophylliens moins affectées par le stress hydrique, une meilleure production de la matière sèche aérienne et nodulaire, des teneurs en proline plus élevées, une meilleure efficacité d’utilisation de la symbiose rhizobienne. De ce fait ces caractères pourront servir de critères de sélection pour la tolérance au stress hydrique chez la fève et la luzerne. Mots clés : Fève, Luzerne, Stress hydrique, Croissance, Symbiose, Fixation de N2

La traducción y el hispanismo argelino. Situación y perspectivas

The objective of this article is to think on the issue of translation in the reinforcement of the Algerian Hispanism movement. The approach is based upon the presentation of the translation panorama on the Algerian works into Spanish, insisting on the fact that the statistics are scarce, those which are interested in the translation movement between Arabic and Spanish, taking also into consideration the particularities of the Algerian case in which the language of expression, besides Arabic, is French. Thus, this phenomenon has affected the transmission of the Algerian literature in Spain, i.e, the literar production has been omitted from its most important part which is literature written in the Arabic language.El propósito de este artículo es reflexionar sobre la aportación de la traducción en el refuerzo del movimiento hispanista argelino. El enfoque se centró sobre la presentación del panorama de la traducción de las obras argelinas a la lengua española, haciendo hincapié sobre la escasez de las estadísticas que se interesan por el movimiento de la traducción entre las lenguas árabe y española, tomando igualmente en consideración la especificidad del caso argelino cuya lengua de expresión, además del árabe, es la lengua francesa, y lo que supuso este fenómeno en la transmisión de la literatura argelina en España, que fue amputada de una gran parte de su producción arabófona

STUDENTS’ ANXIETY IN FOREIGN LANGUAGE LEARNING ENVIRONMENTS: ONLINE VERSUS ON-SITE CLASSROOMS

During the pandemic of COVID-19, the Algerian higher education institutions compelled teachers and students to shift to a blended teaching mode. Accordingly, third-year Licence chemistry students received online and on-site lectures among which English for Specific Purposes lectures. This sudden transition from face-to-face to online teaching affected university students namely at the emotional level which led this research to explore the impact of both modes of course delivery on students’ affective filter more precisely on anxiety. A correlational research design was used to understand the relationship between anxiety and the learning environment. Two anxiety tests on online and on-site learning were administered to 16 chemistry students receiving English for Specific Purposes courses. The current research findings revealed that there is no significant difference in the students’ level of anxiety whether learning online or in the traditional classroom. These findings call for future implications of applying practical techniques and strategies to reduce anxiety in both learning environments to create a suitable and supportive atmosphere that works for better comprehensible input for university students