Functional diversity of the macro‑invertebrate community in the port area of Kerkennah Islands (Tunisia)

The harbour area of Sidi Youssef in Kerkennah islands is characterized by specific anthropogenic pressures linked to fishing activities. To study the functional diversity of benthic macro invertebrates, 10 stations located around the port and along the ship canal were sampled by SCUBA diving. Collected invertebrates were identified, counted and preserved. For the functional organization of the community, the most common biodiversity indices and functional groups were assessed at each station, and main physical and chemical parameters were measured. Results showed that the main apparent anthropogenic stress, that could lead to negative impacts on the studied area, was related to dredging/harbour activities. Suspension feeders, consisting essentially of polychaetes, which may be disturbed by water turbidity, dominated the stations farthest from the port, where the intensity of harbour activities is obviously reduced. On the contrary, carnivores dominated inside the port, possibly benefiting from fish scraps discarded at the area, while stations close to the port appeared to be more balanced trophically. The applied biotic indices showed that the area is in good ecological status, except of the navigation channel and the port entrance, which were slightly degraded

Numerical and Experimental Studies of Simple Geometries in Slamming

peer reviewe

Letter to the Editor: Critical analysis of the published literature about the effects of Ramadan intermittent fasting on healthy children’s physical capacities

No Abstrac

GENERATING FUNCTIONS OF THE PRODUCT OF 2-ORTHOGONAL CHEBYSHEV POLYNOMIALS WITH SOME NUMBERS AND THE OTHER CHEBYSHEV POLYNOMIALS

In this paper, we give the generating functions of binary product between 2-orthogonal Chebyshev polynomials and kFibonacci, k-Pell, k-Jacobsthal numbers and the other orthogonal Chebyshev polynomials

The Effects of Vapor Gard on some Physiological Traits of Durum Wheat and Barley Leaves under Water Stress

The use of antitranspirants is one method of mitigating water while increasing the yield of cereal crops. Experiments were carried out on a durum wheat (Triticum durum L.) variety (Karim) and a barley (Hordeum vulgare L.) variety (Rihane) to study the effects of Vapor Gard (VG; di-1-p-menthene), an antitranspirant, on two physiological traits at two different growth stages. The study was conducted in a glasshouse under water stress and VG was sprayed twice at three concentrations (5, 7, and 10%) at tillering and stem elongation stages. VG spray reduced the effect of water stress on durum wheat and barley varieties. Leaf water potential (LWP) was significantly increased, albeit at different rates, for the two cereal species. However, no significant change was observed for photosynthetic rate (PR). These results favor the use of VG although more studies are recommended on other physiological traits to strongly support the application of this antitranspirant

Synthesis and photophysical properties of new reactive fluorophenanthrenes

A series of six new suitably functionalized fluorophenanthrene derivatives were synthesized through a simple procedure, making use of inexpensive starting materials under mild conditions. The target phenanthrenes were characterized by 1H and 13C NMR and FT-IR spectroscopies. UV–Vis absorption and photoluminescence of these phenanthrenes were evaluated in solutions. A notable behavior and a strong fluorescence in the blue region of the visible spectrum were observed, making them potential candidates for organic light-emitting diode technology or advanced materials. Their electrochemical behavior was also experimentally examined in solution, demonstrating an important charge transfer interaction owing to their ${\pi }$-conjugated electronic system

Synthesis and photophysical properties of new reactive fluorophenanthrenes

A series of six new suitably functionalized fluorophenanthrene derivatives were synthesized through a simple procedure, making use of inexpensive starting materials under mild conditions. The target phenanthrenes were characterized by 1H and 13C NMR and FT-IR spectroscopies. UV–Vis absorption and photoluminescence of these phenanthrenes were evaluated in solutions. A notable behavior and a strong fluorescence in the blue region of the visible spectrum were observed, making them potential candidates for organic light-emitting diode technology or advanced materials. Their electrochemical behavior was also experimentally examined in solution, demonstrating an important charge transfer interaction owing to their ${\pi }$-conjugated electronic system

On the stability of standing waves of Klein-Gordon equations in a semiclassical regime

We investigate the orbital stability and instability of standing waves for two classes of Klein-Gordon equations in the semi-classical regime.Comment: 9 page

Problématique de la régénération naturelle du Prunus avium au nord-ouest de la Tunisie: Influence des facteurs topographiques et édaphiques

The wild cherry (Prunus avium) is a species very appreciated in cabinet making or as root stock for the cherry tree plantations in the Tunisian northwest. Prunus avium is endangered due to its excessive use by local population. It thus seemed necessary to study the process of the natural regeneration by seed of this species. The obtained results showed that the highest rates of regeneration in small plots were observed at medium altitude (400-600 m), with low slope, exposed northward and in loamy soils. This study allowed us to conclude on the importance of the role played by the environment parameters and other climatic factors such as the minimal and maximal temperature in the natural regeneration of this species in our study zone. To be able to conserve and develop Tunisian wild cherries, we recommend using other techniques of multiplication such as cuttings of root segments. Key words: Wild cherry, Tunisia, parameters of the medium, multiplication by sowingLe merisier (Prunus avium) est une espèce très prisée en ébénisterie ou comme porte greffe pour le cerisier dans le nord-ouest tunisien. Prunus avium est menacé de disparition due à son l’utilisation abusive par la population locale. Il est donc apparu nécessaire d’étudier le processus de la régénération naturelle par semis de cette espèce. Les résultats obtenus montrent que le taux de régénération par semis le plus élevé est observé sur les placettes à moyennes altitudes (400-600 m), à faible pente, exposé vers le nord-ouest et sur des sols limoneux. Cette étude nous a permis de conclure l’importance du rôle joué par les paramètres du milieu et d’autres facteurs climatiques comme la température minimale et maximale sur la régénération naturelle de cette espèce au niveau de notre zone d’étude. Pour pouvoir conserver et mettre en valeur les merisiers tunisiens, nous préconisons d’utiliser d’autres techniques de multiplication comme le bouturage de segments de racines. Mots clés: Merisier, Tunisie, paramètres du milieu, multiplication par semi