Starost i rast glavoča travaša Zosterisessor ophiocephalus Pallas, 1811 u zaljevu Gabes (Tunis, središnji Mediteran)

Zosterisessor ophiocephalus is currently an important component of the eastern Mediterranean inshore fisheries. In Tunisia it was recorded for the first time in the Gulf of Gabes in 1993, where it is now an important fished species. In this study age and growth parameters were determined in the Gulf of Gabes (southeast of Tunisia) based on otolith analysis of 824 specimens caught between September 2006 and August 2007. Monthly changes in marginal increments, determined from alternation of macroscopic opaque and translucent bands, of Zosterisessor ophiocephalus sagittae were examined. These results allowed us the estimation of the approximate age to the appearance of each annulus. The observed age was 6 years old for both sexes. Von Bertalanffy parameters based on length at age data were TL∞ = 24.83 ± 1.69 cm, K = 0.19 ± 0.03 year-1 and t0 = - 0.91 ± 0.12 for males and TL∞ = 24.13 ± 1.17 cm, K = 0.20 ± 0.02 year-1 and t0 = - 0.80 ± 0.09 for females. The length-weight relationship for both sexes of Zosterisessor ophiocephalus is Wt = 0.021 TL 2.789. The size at which 50% of females and males matured was respectively 12.65 cm and 13.91 cm total length (TL). The age at which 50% of females and males matured was respectively 2.9 and 3.5 years.Zosterisessor ophiocephalus je trenutno važna komponenta priobalnog ribolova istočnog Mediterana. U Tunisu je prvi put zabilježen u zaljevu Gabes 1993. godine, gdje je sada važna ribolovna vrsta. U ovoj studiji određivani su parametri starosti i rasta u zaljevu Gabes (jugoistočno od Tunisa) na temelju analize otolita 824 primjerka, ulovljenih između rujna 2006. i kolovoza 2007. godine. Starost je utvrđena na temelju fosilnih naraštajnih prstenova na otolitima (sagitta) vrste Zosterisessor ophiocephalus. Ovi rezultati su nam omogućili procjenu približne starosti pojavom svakog prstena kruga /annulus. Utvrđene su najstarije jednike koje su imale 6 godina za oba spola. Von Bertalenffyjevi parametri zasnovani na podatcima o duljini pri određenoj starosti bili su; TL∞ = 24.83 ± 1.69 cm, K = 0.19 ± 0.03 godina-1 i t0 = - 0.91 ± 0.12 za mužjake i TL∞ = 24.13 ± 1.17 cm, K = 0.20 ± 0.02 godina-1 i t0 = - 0.80 ± 0.09 za ženke. Dužinsko-maseni odnos za oba spola vrste Zosterisessor ophiocephalus je Wt = 0,021 TL 2.789. Veličina kod koje 50% ženki i mužjaka sazrijeva bila je 12,65 cm i 13,91 cm ukupne duljine (TL). Dob kod koje 50% ženki i mužjaka sazrijeva je između 2,9 i 3,5 godina starosti

Using Fourier-based shape alignment to add geometric prior to snakes

International audienceIn this paper, we present a new algorithm of snakes with geometric prior. A method of shape alignment using Fourier coefficients is introduced to estimate the Euclidean transformation between the evolving snake and a template of the searched object. This allows the definition of a new field of forces making the evolving snake to have a shape similar to the template one. Furthermore, this strategy can be used to manage several possible templates by computing a shape distance to select the best one at each iteration. The new method also solves some well-known limitations of snakes such as evolution in concave boundaries, and enhances the robustness to noise and partially occluded objects. A series of experimental results is presented to illustrate performances

Fourier-based geometric shape prior for snakes

International audienceA novel method of snakes with shape prior is presented in this paper. We propose to add a new force which makes the curve evolve to particular shape corresponding to a template to overcome some well-known problems of snakes. The template is an instance or a sketch of the researched contour without knowing its exact geometric pose in the image. The prior information is introduced through a set of complete and locally stable invariants to Euclidean transformations (translation, rotation and scale factor) computed using Fourier Transform on contours. The method is evaluated with the segmentation of myocardial scintigraphy slices and the tracking of an object in a video sequence

Hypoxia-Induced Molecular and Cellular Changes in the Congenitally Diseased Heart: Mechanisms and Strategies of Intervention

Tissue hypoxia plays a critical role in the pathobiology of congenital heart diseases, especially with regard to cyanotic patients. Here, we describe the cellular and molecular mechanisms induced by hypoxia in the diseased heart, with particular attention to the metabolic and functional changes that underlie the hypoxia-induced right ventricle remodelling. The role of reactive oxygen species in transcriptomic changes, DNA damage, contractile dysfunction and extracellular matrix remodelling will be addressed. Furthermore, the reoxygenation injury, which occurs when oxygen is reintroduced upon initiation of cardiopulmonary bypass, will be discussed. This allows a better understanding of the risks associated with the reoxygenation injury in children undergoing open-heart surgery and helps to improve strategies of intervention for myocardial protection

Pojava imposeksa kod vrste Bolinus brandaris (Gastropoda: Muricidae) duž gradijenta priobalno/otvoreno more u zaljevu Gabes (južni Tunis, središnji dio Sredozemnog mora)

The present study provides the first data available on imposex in a gastropod species caught offshore the Tunisian coast. Imposex was analysed in the purple dye murex (Bolinus brandaris) from ten collecting sites offshore the Gulf of Gabès (southern Tunisia, Central Mediterranean Sea). From a total of 584 individuals analysed, females outnumbered males, leading to a female-biased sex ratio (1 F:0.7 M). Among the 353 females analysed, 117 were affected by imposex. On the whole, these females presented low to moderate imposex incidence (I%=33.1) and severity (FPLI=0.3, RPLI=2.6 and VDSI=0.8). The study revealed that imposex is a widespread phenomenon in the Gulf of Gabès and identified a clear inshore/offshore gradient in the imposex indices of B. brandaris. Regression analysis detected highly significant negative correlations between imposex indices and the distance to the coastline and depth of the collecting sites. Principal components analysis highlighted the specific influence of the distance to the major harbours, either in number of calling vessels (commercial harbour of Sfax) or shipping tonnage (oil terminal of Skhira). This inshore/offshore gradient of imposex development in B. brandaris reflects marked spatial variation in pollution by organotin compounds associated to the shipping activity. Overall, the study provides valuable baseline data for assessing the future evolution of imposex in B. brandaris, and subsequently the spatial and temporal trends of pollution by organotin compounds offshore the Gulf of Gabès.U radu se iznose prvi podaci o pojavi imposeksa kod puževa uhvaćenih u otvorenom moru Tunisa. Imposeks je analiziran na jedinkama bodljikavog volka (Bolinus brandaris) prikupljenim na deset postaja u otvorenom moru zaljeva Gabes (južni Tunis, središnji dio Sredozemnog mora). Ukupno su analizirane 584 jedinke, a omjer spolova je bio u korist ženki (1 Ž: 0,7 M). Od 353 analizirane ženke, 117 ih je bilo pogođeno imposeksom. Općenito, učestalost imposeksa kod ženki je bila niska do osrednja (I%=33.1) i jačina (FPLI=0.3, RPLI=2.6 i VDSI=0.8). Studija je pokazala da je pojava imposeksa raširena u zaljevu Gabes te je utvrđen jasan gradijent pojavnosti imposeksa kod B. brandaris na relaciji priobalno/otvoreno more. Regresijskom analizom otkrivene su vrlo značajne negativne korelacije između pojavnosti imposeksa, udaljenosti od obalne linije te dubine na kojoj se uzorkovalo. Analiza glavnih komponenti (PCA) istaknula je određeni utjecaj udaljenosti od glavnih luka, i to ovisno o broju plovila (komercijalna luka Sfax) ili brodske tonaže (naftni terminal Skhira). Ovaj priobalno/otvoreno more gradijent razvoja imposeksa odražava značajne prostorne varijacije kod onečišćenja organskim spojevima kositra povezanih s pomorskom djelatnošću. Ova studija pruža vrijedne temeljne podatke za buduću procijenu razvoja imposeksa kod vrste B. brandaris, te prostorno i vremenskih trendova onečišćenja organskim spojevima kositra u otvorenom moru zaljeva Gabes

Raspodjela, brojnost i biološki parametri vrste Cerastoderma glaucum (Mollusca: Bivalvia) duž obale zaljeva Gabes (Tunis, središnji Mediteran)

The cockle Cerastoderma glaucum (poiret, 1789) represents one of the most common marine mollusc species present in soft bottom infralittoral assemblages in Tunisian waters. The status of the species is still poorly known and there is a knowledge gap about its distribution, abundance and biological parameters. The significant ecological role of C. glaucum in the ecosystem and its possible future commercial interest requires a better knowledge of its stock. This study aimed to investigate the distribution, abundance and biology of these cockles along the Gabes coast. Cockles were collected, treated and data were analysed. In terms of geographical occupation, maps of the population distribution were drawn. The results showed a scattered distribution pattern of the species according to location ranging between 0 and 270 individuals per square meter. The consequence was a remarkable biomass which represented 1290±326 tons of total fresh weight and high abundance levels reaching over 403±104 million individuals estimated in the area of 3723 hectares. The distribution of the species has also been investigated in consideration with the size which varied markedly according to location, while the shell length ranged between 5 and 37 mm. Samples presented a balanced sex ratio, with males dominating among smaller individuals and females predominating in larger size-classes contrary to previous findings on this species. The size at which 50% of the population reached maturity was 14.29 and 16.59 mm SL for males and females, respectively. Findings of the current study suggest that C. glaucum well proliferates in southern Tunisian waters.Srčanka Cerastoderma glaucum (poiret, 1789) predstavlja jednu od najčešćih vrsta morskih mekušaca prisutnih u infralitoralnim zajednicama mekog dna u vodama Tunisa. Status ove vrste je još uvijek nedovoljno poznat te postoje praznine u znanju o njenoj raspodjeli, brojnosti i biološkim parametrima. značajna ekološka uloga vrste C. glaucum u ekosustavu i mogući budući komercijalni interes zahtijevaju bolje znanje o njenom stoku. Ova studija je usmjerena na istraživanje raspodjele, brojnosti i biologije srčanki duž obale zaljeva Gabes. Srčanke su sakupljane, obrađene i analizirani su podatci. u pogledu geografske rasprostranjenosti, nacrtane su karte raspodjele populacije. rezultati su pokazali raspršeni uzorak raspodjele vrste prema lokaciji u rasponu od 0 do 270 jedinki po kvadratnom metru. posljedica je bila izvanredna biomasa koja je predstavljala 1290±326 tone ukupne svježe mase i visoke razine brojnosti koje dosežu preko 403±104 milijuna jedinki procijenjenih na području od 3723 hektara. raspodjela vrste također je bila istraživana s obzirom na veličinu koja značajno koleba ovisno o lokaciji, dok je dužina ljušture bila u rasponu između 5 i 37 mm. primjerci su predstavili uravnotežen omjer spolova, sa mužjacima koji prevladavaju među manjim jedinkama i ženkama koje prevladavaju u razredima veće veličine, suprotno prijašnjim saznanjima za ovu vrstu. veličina kod koje 50% populacije doseže zrelost bila je između 14,29 i 16,59 mm Sl (shell length - dužine ljušture) za mužjake i ženke. Saznanja ove studije navode na to da se vrsta C. glaucum uspješno razmnožava u vodama južnog Tunisa

Reproduktivna biologija vrste Diplodus vulgaris (Teleostei, Sparidae) u vodama južnog Tunisa (središnji Mediteran)

The reproduction of the common-two banded seabream (N=916), Diplodus vulgaris, was studied in the Gulf of Gabes (Tunisia). The length at the first maturity averages 13.64 ± 0.18 cm for males and 13.84 ± 0.17 cm for females. Macroscopic examination of gonads and gonad-somatic index indicated that spawning occurs once a year between November and February with peak activity in November and December. Fecundity estimates ranged from 8 400 to 30 800 oocytes.Razmnožavanje fratra (N=916) Diplodus vulgaris, istraživano je u zaljevu Gabes (Tunis). Dužina prve spolne zrelosti je u prosjeku između 13,64 ± 0,18 cm za mužjake i 13,84 ± 0,17 cm za ženke. Makroskopsko ispitivanje gonada i gonadsko-somatskog indeksa pokazuje da se mriješćenje odvija jednom godišnje, između siječnja i veljače sa vrhuncem u studenom i prosincu. Procjene fekunditeta su u rasponu od 8 400 do 30 800 oocita