Etude éco-biologique d’Artémia salina des zones humides de l’Ouest Algérien

L’Artémie (Artémia salina) est une espèce de crustacé vivant dans les lacs salés, les chotts et les marais salants .Elle est en abondance dans les salines de l’ouest Algérien. Ce genre de crustacé est très demandé dans le domaine d’exploitation des ressources hydriques et en aquaculture. Dans le présent travail on a étudié, en premier lieu l’aspect biologique et écologique de ce crustacé dans les salines de Bathioua (wilaya d’Oran) et Oued Djemaa (wilaya de Relizane), en deuxième lieu on a étudié son accommodation à différentes doses de salinité dans un milieu même quand les conditions de vie sont défavorables. L’Artémie salina est capable de produire des cystes qui ont la capacité de donner naissance à une larve appelée nauplius. La résistivité des cystes au stress du milieu en état de cryptobiose, leur permet de subsister à des températures extrêmes. Les nauplius sont distribués dès l’éclosion ou après 24 à 48 h d’enrichissement en protéines et en lipides. Les résultats obtenus lors de ce travail ont montré que le taux de reproduction varie en fonction des changements saisonniers des différents facteurs écologiques et des éléments physico chimiques de son environnement.Mots-clés: Artémia salina, aspect biologique, adaptation, salines, Ouest Algérien. Eco-biological study of Artemia salina wetlands of West AlgeriaThe Artemia (Artemia salina) is a species of crustacean living in salt lakes, chotts and salt marshes. It is in abundance in the salt mines of western Algeria. This kind of crustacean is highly demanded in the fields of water exploitation and aquaculture. In this study, the observation is drawn on the biological and ecological aspects of this crustacean in the salt mines of Bathioua (Oran wilaya) and Oued Djemaa (Relizane wilaya), according to the seasonal variations. Artemia salina is able to produce cysts that have the ability to give birth to a larva called nauplius. The resistivity of cysts at environment stress on cryptobiosis state allows them to survive in extreme temperatures. Nauplii begin hatching after 24 to 48 h enrichment in proteins and lipids. The results obtained in this work showed that the reproduction rate varies according to seasonal changes in different ecological factors and the physical and chemical elements of its environment.Keywords : Artemia salina, biological aspect, adaptation, salt, West Algeria

Transcranial direct current stimulation (tDCS) in the treatment of depression: Systematic review and meta-analysis of efficacy and tolerability

BACKGROUND Transcranial direct current stimulation (tDCS) is a potential alternative treatment option for major depressive episodes (MDE). OBJECTIVES We address the efficacy and safety of tDCS in MDE. METHODS The outcome measures were Hedges' g for continuous depression ratings, and categorical response and remission rates. RESULTS A random effects model indicated that tDCS was superior to sham tDCS (k=11, N=393, g=0.30, 95% CI=[0.04, 0.57], p=0.027). Adjunctive antidepressant medication and cognitive control training negatively impacted on the treatment effect. The pooled log odds ratios (LOR) for response and remission were positive, but statistically non-significant (response: k=9, LOR=0.36, 95% CI[-0.16, 0.88], p=0.176, remission: k=9, LOR=0.25, 95% CI [-0.42, 0.91], p=0.468). We estimated that for a study to detect the pooled continuous effect (g=0.30) at 80% power (alpha=0.05), a total N of at least 346 would be required (with the total N required to detect the upper and lower bound being 49 and 12,693, respectively). CONCLUSIONS tDCS may be efficacious for treatment of MDE. The data do not support the use of tDCS in treatment-resistant depression, or as an add-on augmentation treatment. Larger studies over longer treatment periods are needed

ALADIN is Required for the Production of Fertile Mouse Oocytes

Asymmetric cell divisions depend on the precise placement of the spindle apparatus. In mammalian oocytes, spindles assemble close to the cell's center, but chromosome segregation takes place at the cell periphery where half of the chromosomes are expelled into small, nondeveloping polar bodies at anaphase. By dividing so asymmetrically, most of the cytoplasmic content within the oocyte is preserved, which is critical for successful fertilization and early development. Recently we determined that the nucleoporin ALADIN participates in spindle assembly in somatic cells, and we have also shown that female mice homozygously null for ALADIN are sterile. In this study we show that this protein is involved in specific meiotic stages, including meiotic resumption, spindle assembly, and spindle positioning. In the absence of ALADIN, polar body extrusion is compromised due to problems in spindle orientation and anchoring at the first meiotic anaphase. ALADIN null oocytes that mature far enough to be fertilized in vitro are unable to support embryonic development beyond the two-cell stage. Overall, we find that ALADIN is critical for oocyte maturation and appears to be far more essential for this process than for somatic cell divisions

Penetration testing and thermal behavior of bitumen 35/50 and modified bitumen 13/40

Physical properties of pure bitumen 35/50 and polymer-modified bitumen 13/40 are studied using needle penetration test and differential scanning calorimetry (DSC). In particular, the mechanical response under indentation conditions is achieved as a function of different loads and temperatures. Our results show that lower temperature susceptibility is associated to larger loads but its change is rather small for the tested bitumens. A pure bitumen 35/50 exhibits a single glass transition temperature for different heating rate whereas modified bitumen 13/40 presents two Tg for different heating rate

A decision-support framework to manage a sewer system considering uncertainties

International audienceAsset management (inspection, maintenance and repair or replacement) of infrastructures represents a complex multidimensional problem and constitutes a topical subject for many cities (constrained budget, environmental requirements, risk mitigation …). In this paper, we developed an innovative approach to sewer system management. The proposed approach is based on a multicriteria decision analysis (MCDA) which includes a degradation model considering uncertainties. The resulting tool, called AGORA, enables to assess a sewage system based on a set of technical, social, economic and environmental criteria, whereas considering uncertainties, and to compare different management strategies. The used probability multicriteria framework allows to consider different kinds of operational actions, and notably inspection (gain of information), and to have a rich vision on the system at different time horizon. AGORA is applied to a semi-virtual network

Ressources hydriques sous tension et enjeux de développement durable dans la wilaya de Sidi Bel Abbes (Algérie occidentale)

À l’instar des wilayas du département de l’Ouest algérien, la wilaya de Sidi Bel Abbès souffre de pénurie d’eau. Dans cette région, où les écoulements sont caractérisés par une irrégularité saisonnière et interannuelle importante, les potentialités en eau sont faibles. Les ressources en eau souterraines et superficielles sont insuffisantes à satisfaire les besoins et ne répondent pas aux demandes croissantes de la population qu’elle soit urbaine ou rurale. La wilaya de Sidi Bel Abbès n’a pu supporter le déficit en eau et faire face aux aléas climatiques récents. C’est dans cette optique que les organismes gestionnaires ont fait appel à des transferts d’eau des wilayas limitrophes pour couvrir le manque enregistré ces dernières années. L’étude présentée ici contribue à la mise en place d’une base de données participant à la compréhension des modalités de gestion intra et extra-wilaya. Elle permet par la suite d’analyser les enjeux de cet élément crucial, nécessaire à toute vie et à tout développement socio-économiqueLike the wilayas of west Algerian department, wilaya of Sidi Bel Abbes suffers from water shortage. In this region, where the flows are characterized by a considerable seasonal and irregularity, the water potentials are low. Water resources in ground or surface are insufficient to meet the needs and growing demands of the urban or rural population. The wilaya of Sidi Bel Abbes couldn’t withstand this water deficit and facing the hazards climate changment recently. In this regard the administrative bodies called for water transfer from neighboring wilayas to cover the registered lack in the last years. The study is contributing to make a data base participating to understand ways of intra and extra wilayas water management. so it allows analyzing the issue of this critical factor necessary for the whole life and for socio- economic development

Optimal Carbon NanoTubes concentration incorporated in mortar and concrete

The mechanical properties and microstructure of modified mortar and concrete using Carbon NanoTubes (CNT) are experimentally studied at 7, 14, 28 and 90 curing days. Part of the formulation, CNT are dispersed in a liquid solution. Different concentrations ranging from 0.01% to 0.06% and 0.003% up to 0.01% are used for mortar and concrete, respectively. Mechanical testing of the modified materials reveals that maximum compressive strength is obtained for CNT concentrations close to 0.01%wt and 0.003%wt for mortar and concrete, respectively. The microstructural characterisation of the modified materials suggests that CNT act as bridges between pores and cracks leading to a reduction in porosity and in turn an increase of compressive strength

Amplification effects on the trasmission and reflextion phases in 1D periodic systems

Consiglio Nazionale delle Ricerche - Biblioteca Centrale - P.le Aldo Moro, 7 Rome / CNR - Consiglio Nazionale delle RichercheSIGLEITItal