Neobična pristunost juvenilnih primjeraka vrste Synagrops japonicus u jugozapadnom Mediteranu

This paper reports additional records of the Indo-Pacific fish Synagrops japonicus (Doderlein, 1884) in Western Mediterranean. Twenty juveniles of this species ranging from 4 to 4.8 cm (TL) were caught in Annaba Bay, Algeria, using beach seine, in Summer of 2011 (9 specimens, 4 ≤ TL ≤ 4.6 cm) and 2012 (11 specimens, 4.2 ≤ TL ≤ 4.8 cm). Some hypotheses on the origin of this unusual presence are discussed.U ovom radu se navode dodatni nalazi vrste Synagrops japonicus (Doderlein, 1884) u zapadnom Mediteranu. Uhvaćeno je dvadeset juvenilnih primjeraka ove vrste u rasponu od 4 do 4,8 cm (TL) u Annaba zaljevu, Alžir, pomoću obalne mreže potegače, u ljeto 2011. godine (9 primjeraka, 4 ≤ TL ≤ 4,6 cm) i 2012. (11 primjeraka, 4.2 ≤ TL ≤ 4,8 cm). U radu su iznesene neke hipoteze o podrijetlu ove neobične prisutnosti

Composition and variations of the fish assemblage of Posidonia oceanica (L.) Delile, seagrass meadows in Annaba bay (Algeria)

During an annual cycle (July 2004 - June 2005), two coastal sites, one far away from anthropic action (site A : Aïn Achir) and the other subjected to immediate discharge of waste water (site B : la Caroube), were sampled during the day (8 h -18 h) and by night (19 h - 7 h), with a net (50 m long, 2 m high) located at a depth of -5 m. According to the frequency of fish species captured, their ecological status was determined. The Shannon-Weaver diversity index (H’) was calculated to better understand the structure and organization of fish assemblages in both sites. In site A, 19 species belonging to 8 families were fished during the day. At night, the fish assemblage was represented by 15 species and 9 families. The family Sparidae was the most diversified, followed by Labridae and Serranidae. Labridae were the most numerous family by day and by night. Numbers of species and individuals collected in site B during the day (16) as well as by night (11) were significantly lower than those of site A. During daytime, diversity (H’) and equitability (R) indices were respectively 2.51 and 0.33 in site A and of 2.87 and 0.43 in site B. At night, diversity index was lower (site A : 0.64 and site B : 2.55) and equitability was close to 0.41 in the two sitesAu cours d'un cycle annuel (juillet 2004 - juin 2005), deux sites côtiers, l'un éloigné de l'action anthropique (site A: Aïn-Achir) et l'autre recevant les rejets directs des eaux usées de la ville d'Annaba (site B: la Caroube), ont été échantillonnés de jour et de nuit à l'aide d'un filet trémail. En fonction de sa fréquence, le statut écologique de chaque espèce a été déterminé. L'indice de diversité biologique de Shannon-Weaver (H') a été calculé pour mieux comprendre la structure et l'organisation du peuplement de poissons dans les deux sites. Dans le site A, 19 espèces appartenant à 8 familles ont été pêchées de jour. La nuit, le peuplement ichtyologique est représenté par 15 espèces et 9 familles. La famille des Sparidés est la plus diversifiée, suivie de celle des Labridés et des Serranidés. Les Labridés sont les mieux représentés numériquement, aussi bien de jour que de nuit. Dans le site B, les nombres d'espèces et d'individus capturés, aussi bien de jour (16 espèces) que de nuit (11 espèces), sont nettement inférieurs à ceux obtenus dans le site A. De jour, les indices de diversité (H') et d'équitabilité (R) sont respectivement de 2,51 et de 0,33 dans le site A et de 2,87 et de 0,43 dans le site B. La nuit, l'indice de diversité est plus faible (site A: 0,64 ; site B: 2,55) et l'équitabilité est proche de 0,41 dans les deux sites

Two-Photon absorption cross-section measurement by thermal lens and nonlinear transmission methods in organic materials at 532 nm and 1064 nm laser excitations

Experimental results concerning two-photon absorption (TPA) cross-section measurement using nonlinear transmission (NLT) method and a new pump-probe mode-mismatched thermal lens (TL) scheme, in picosecond regime are reported. Both methods are used in a prospect of comparison. Values of the TPA coefficient and cross-section in three common solvents (Chloroform, Benzene and Nitrobenzene) and new synthesized perylenediimide derivatives (PDI) at 532nm and 1064nm wavelengths are given

New cyclopropano 70 fullerene derivatives for the photovoltaic application

New cyclopropano 70 fullerenes derivatives were synthesised for photovoltaic (PV) application. The organic PV cells realized with these molecules blended with RR-P3HT polymer provided improved characteristics: 1.5% conversion efficiency (eta%), 9.29 mA/cm2 current density, 0.51 V open circuit voltage and 0.34 fill factor. The IPCE spectrum for P3HT: cyclopropano 70 fullerene cells shows a new peak around 430 nm with 71% external quantum efficiency. This explains the increased current density

Study of Two-Photon absorption in Organic Materials by thermal lensing and nonlinear transmission measurements

Experimental investigations of two-photon absorption (TPA) cross-section using nonlinear transmission (NLT) and a new pump-probe mode-mismatched thermal lens (TL) scheme, in the picosecond regime are reported. Both methods are used in a prospect of comparison. Values of the TPA coefficient and cross-section in perylenediimide derivatives (PDI) at 532 nm and 1064 nm wavelengths are given

How far does the central bank influence its economies? The example of Algeria

This study focused on Algeria and it looked at how education quality affected the knowledge economy. The theoretical anchor was the endogenous or new growth hypothesis. Secondary sources were used to get panel-structured data that spanned 48 Algerian provinces in 22 years (1999–2020). The equations were estimated using the fixed-random effect model and Hausman test, Also the Kao (Engle Ganger-based) cointegration test proved that the series did indeed have a long-run connection. The findings indicated that the knowledge economy was boosted by a rise in students’ Baccalaureate and Intermediate test success rates. This is due to the fact that a rise in exam success rates indicates that individuals at various educational levels are now receiving education of a higher caliber, and the economy depends on this caliber of education. The rise in students and professors is a sign that there are more knowledgeable people and specialized educators accessible to fuel the knowledge economy. As more educated citizens pass their exams and graduate from college, they are hired from the labor market into industries as significant production factors whose skills, values, and knowledge acquired through specialized training are expected to promote machine handling and coordination of other human and nonhuman production factors to fuel the knowledge economy. Teachers should be provided with ongoing professional development opportunities to help them provide instruction at all educational levels, according to a recommendation. This would improve their ability to educate and inspire students and help them do better on their intermediate and baccalaureate exam

Study of multiphoton absorption processes in a perylenediimide derivative using thermal lensing technique Study of multiphoton absorption processes in a perylenediimide derivative using thermal lensing technique

Two multiphoton absorption processes were revealed in a perylenediimide derivative, at the wavelength of 1064 nm, by using the thermal lens technique. One of the observed multiphoton processes is two photon absorption (TPA) while the second is a four photons process. The value of the measured TPA coefficientis β=0.12×10-10 cm W-

Des possibilités d'emploi du sperme de taureau transporté de France pour l'insémination artificielle dans les territoires d'Outre-mer

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