LA PREVENTION DU RISQUE DE DEFAUT DANS LES BANQUES TUNISIENNES. Analyse comparative entre les méthodes linéaires classiques et les méthodes de l'intelligence artificielle : les réseaux de neurones artificiels

Ce papier porte sur le risque de non remboursement des crédits de gestion par une banque commerciale tunisienne. Ainsi, la maîtrise du risque de défaut des crédits est devenue l'un des axes stratégiques majeurs de la gestion des organismes bancaires. Ce papier se fixe pour objectif de comparer le pouvoir prédictif de trois méthodes de prévision du risque à savoir : le scoring, la régression logistique et les réseaux de neurones artificiels. Nous avons utilisé une base de données composée de 1435 dossiers de crédit octroyés aux entreprises industrielles tunisiennes en 2003,2004,2005 et 2006. Les résultats montrent la supériorité des réseaux de neurones artificiels par rapport aux autres méthodes classiques en matière de détresse financière des firmes emprunteuses. Dans ce sens nous avons obtenu un taux de bon classement global de 97% pour l‟échantillon d‟apprentissage et 89.9% pour l‟échantillon testSecteur bancaire scoring ; régression logistique, panel, réseaux de neurones, la prévision du risque de défaut

158 Prothetic abcess complicating Infective endocarditis

The cardiac abscess formation is appraised to 20–30% during the infectious endocarditis (IE). It is more frequent during prosthesis endocarditis and it can reach 60%. The prognosis is generally reserved. Objective To determine echocardiographic, bacteriological and evolutive features of prothetic IE complicated of abscess.Retrospective study including 51 patients having certain or probable IE according to Duke criterias between 2002 and 2005. At 9 patients (17,64%) the endocarditis was complicated of prothetic abscess. It was about 6 men and 3 women with a middle age of 39 ± years. IE was la ate IE in 5 cases. Clinical and biological infectious syndrome was constant. Isolated germs were staphylococcus aureus in 2 cases, GRAM négatif Bacillus in 2 cases. Culture negative endocarditis were noted in 5 cases. Brucellosis serology was positive at one patient. Prothetic abcess was diagnosed by transthoracic echocardiography (TTE) at 2 patients and by transesophagal echocardiography (TEE) at all patients.The abcess was localized on the aortic prosthesis at 5 patients, mitral prothesis at 3 patients and mitroaortic prothesis at one patient. TEE identified annular abcess at 2 patients and a myocardial abcess at 1 patient. Secondary septic localizations were noted at 6 patients: 4 cerebral abscesses, 2 splenic localization, a renal localization and an articular localization. High degree atrioventricular blocks were observed at 3 patients. The recourse to the surgery was frequent (7 patient/9 patient). It was an emergent sugery at 2 patients because of a heart failure. For the others, the indication for surgery was medical failure treatment at a mean delay of 19 days. The evolution was fatal at 5 patients. and the evolution was favorable at the others.Prothetic endocarditis complicated of abscess are serious requiring frequently a prothetic replacement, a very high risked surgery. TEE must be systematic at all patients carrier of prosthesis if they have infectious syndrome in order to carry the early diagnosis of IE and to avoid abcess formation

Phytochemical profile and antioxidant capacity of virgin olive oil obtained from the olive cultivar 'Roghiani' from different regions of northern Libya

The aim of this work was to determine the fatty acids (FA), tocopherols, phenols, and antioxidant capacity (AC) of five virgin olive oils (VOO) obtained from the olive cultivar 'Roghiani', from different regions of northern Libya during the crop year 2015. The parameters determined for the oils were investigated for the first time. Seven principal FAs were detected in the VOO samples. Oleic, palmitic, and linoleic acids were the dominant ones. The highest percentage of palmitic acid was found in Tripoli VOO (P lt = 0.05). Oleic acid was dominant in all the VOO samples. Gharyan VOO possessed the highest value of oleic acid, O/L ratio, monounsaturated fatty acids (MUFA), total phenols content (TPC), total tocopherol and tocotrienol contents (TTC), and AC(DPPH)% (P lt = 0.05). A strong positive relationship between TPC and (AC) as (1/EC50DPPH) was observed, (r) was +0.831. On the other hand, (1/EC50DPPH) showed a positive correlation with TTC, (r) was +0.768

Monitoring the volatile and hydrophilic bioactive compounds status of fresh and oxidized Chemlali virgin olive oils over olive storage times

The virgin olive oils (VOOs) under examination were from the main Tunisian cultivar ‘Chemlali’. Olive fruits used for oil production were stored in plastic containers for four weeks at ambient temperature. Hydrophilic bioactive compounds and volatile profiles of the corresponding oils were analyzed. Chemometric analysis showed that VOO obtained from fruits stored during one week is similar to that of freshly harvested fruits. They preserved their bioactive and volatile molecular markers of freshness with the predominance of the secoiridoid aldehydic form of oleuropeine aglycon, and the C6⁠ lipoxygenase products. However, VOO obtained from fruits stored for a long time, showed degradation of the derivatives of oleuropeine and ligstro- side aglycons, a decrease in the lignan, and flavonoid groups, whereas phenolic acids showed a remarkable in- crease. The volatile profile was characterized by a decrease in the LOX products, and biosynthesis of the volatile molecular markers of oxidation C7⁠ -C1⁠ 0 aldehydes (nonanal, decanal, (Z) and (E)-2-heptenal, (E)-2-octenal, and (E,E)-2,4-heptadienal), and hydrocarbons (n-dodecane, and n-tetradecane). Mono and sesquiterpenes showed also an increase over storage time. Consequently, and in order to avoid deterioration of VOO composition, chemometric analysis showed that the olive fruits should be processed as soon as possible after being harvested, with a maximum storage time of one week