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Effect of Salinity on Germination,Seedling Growth and Acid Phosphatase Activity in Lettuce

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American Journal of Plant Sciences 2015年第1期6卷 57-63页

作者： Nawel Nasri Issam Saidi rym kaddour Mokhtar Lachaal Physiologie et Biochimie de la Tolérance au Sel des Plantes Faculte des Sciences de TunisCampus UniversitaireTunisTunisia

The impact of salt stress (NaCl 100 mM) on two lettuce varieties Romaine and Vista was conducted at germination and early seedling stages. The seeds of lettuce varieties were provided by the Seed Laboratory of Tunisian Ministry of Agriculture. The seeds were germinated in Petri dishes with double filter paper in distilled water (control) or NaCl solution (100 mM) for 5 days. The result showed that salinity significantly affected percentage and rate of germination in Vista variety but 100% of germination was found in Romaine. Length and fresh weight of root and shoot were reduced significantly with salt treatment in two lettuce varieties. Regarding biochemical analysis, acid phosphatase activity in root increased in Romaine and decreased in Vista. In shoot, this activity showed no difference with the control in the two varieties. However in cotyledons, and during 24 hours after germination, salinity decreased acid phosphatase activity in both varieties whereas in the later hours (48 - 96 h) this activity reached the value of the control in Romaine and Vista.

关键词： Acid Phosphatase Germination Lettuce Salinity Seedling

Characterization of component interactions in two-stage axial turbine

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Chinese Journal of Aeronautics 2016年第4期29卷 893-913页

作者： Adel Ghenaiet kaddour Touil Laboratory of Energetics and Conversion Systems Faculty of Mechanical Engineering University of Sciences and Technology Houari Boumediene Laboratory of Thermal Power Systems Applied Mechanics

This study concerns the characterization of both the steady and unsteady flows and the analysis of stator/rotor interactions of a two-stage axial turbine. The predicted aerodynamic performances show noticeable differences when simulating the turbine stages simultaneously or separately. By considering the multi-blade per row and the scaling technique, the Computational fluid dynamics(CFD) produced better results concerning the effect of pitchwise positions between vanes and blades. The recorded pressure fluctuations exhibit a high unsteadiness characterized by a space–time periodicity described by a double Fourier decomposition. The Fast Fourier Transform FFT analysis of the static pressure fluctuations recorded at different interfaces reveals the existence of principal harmonics and their multiples, and each lobed structure of pressure wave corresponds to the number of vane/blade count. The potential effect is seen to propagate both upstream and downstream of each blade row and becomes accentuated at low mass flow rates. Between vanes and blades, the potential effect is seen to dominate the quasi totality of blade span, while downstream the blades this effect seems to dominate from hub to mid span. Near the shroud the prevailing effect is rather linked to the blade tip flow structure.

关键词： CFD FFT analysis Pressure fluctuations Two-stage axial turbine Unsteady flows Vane/blade interactions

SVM Model Selection Using PSO for Learning Handwritten Arabic Characters

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Computers, Materials & Continua 2019年第9期61卷 995-1008页

作者： Mamouni El Mamoun Zennaki Mahmoud Sadouni kaddour Département Informatique Universitédes Sciences et de la Technologie d’Oran Mohamed Boudiaf USTO-MB BP 1505 El M’naoeur31000OranAlgérie

Using Support Vector Machine(SVM)requires the selection of several parameters such as multi-class strategy type(one-against-all or one-against-one),the regularization parameter C,kernel function and their *** choice of these parameters has a great influence on the performance of the final *** paper considers the grid search method and the particle swarm optimization(PSO)technique that have allowed to quickly select and scan a large space of SVM parameters.A comparative study of the SVM models is also presented to examine the convergence speed and the results of each *** is applied to handwritten Arabic characters learning,with a database containing 4840 Arabic characters in their different positions(isolated,beginning,middle and end).Some very promising results have been achieved.

关键词： SVM PSO handwritten Arabic grid search character recognition

Solitary Endobronchial Papilloma Mimicking a Neoplastic Lesion

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Open Journal of Respiratory Diseases 2018年第3期8卷 38-42页

作者： Smadhi Hanen Khalfallah Ikbel Diouani Mohamed Fethi Abdennadher Mahdi Attia Monia Ayadi-kaddour Aida Megdiche Mohamed Lamine Department of Pneumology Ibn Nafis Abderrahman Mami University Hospital Ariana Tunisia Faculté de Médecine de Tunis Université Tunis El Manar Tunis Tunisia Faculté des Sciences de Bizerte Université de Carthage Carthage Tunisia Laboratoire d’Epidémiologie et de Microbiologie Vétérinaire Institut Pasteur de Tunis Tunis Tunisia Department of Thoracic Surgery Abderrahman Mami University Hospital Ariana Tunisia Department of Radiology Abderrahman Mami University Hospital Ariana Tunisia Department of Pathology Abderrahman Mami University Hospital Ariana Tunisia

Papilloma is a rare benign tumor. Laryngeal location is the most frequent. The bronchial involvement remains unusual. It represents 0.38% of pulmonary tumors. We report the case of a 39-year-old, smoker man, who consulted for a cough following during six months with persistent radiological opacity despite antibiotic treatment. The physical examination was without particularities. Flexible bronchoscopy revealed a swollen endobronchial lesion completely obstructing the orifice of the intermediate trunk. Bronchial biopsies at this level showed inflammatory mucosa. The chest CT scan objectified an endobronchial tissular mass in the intermediate trunk. Pulmonary neoplasia was suspected. Diagnostic and therapeutic surgery was performed. Histopathological examination concluded to an endobronchial squamous papilloma.

关键词： Papilloma Smoking Lung Cancer Surgery

Unusual Location of Coelomic Cysts

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Open Journal of Respiratory Diseases 2018年第3期8卷 33-37页

作者： Smadhi Hanen Ben Jemai Emna Diouani Mohamed Fethi Abdennadhar Mahdi Attia Monia Ayadi-kaddour Aida Megdiche Mohamed Lamine Department of Pneumology Ibn Nafis Abderrahman Mami University Hospital Ariana Tunisia Faculté de Médecine de Tunis Université Tunis El Manar Tunis Tunisia. Faculté des Sciences de Bizerte Université de Carthage Carthage Tunisia. Laboratoire d’Epidémiologie et de Microbiologie Vétérinaire Institut Pasteur de Tunis Tunis Tunisia Department of Thoracic Surgery Abderrahman Mami University Hospital Ariana Tunisia Department of Radiology Abderrahman Mami University Hospital Ariana Tunisia Department of Pathology Abderrahman Mami University Hospital Ariana Tunisia

Intrathoracic mesothelial cysts are congenital lesions due to an abnormal development of the pericardial coelom. They are generally unilocular and can develop in various sites. We describe a case of multicystic lesions in the anterior mediastinum of a 53-year-old woman discovered in a context of an encysted pleural effusion. Chest computed tomography (CT) scan revealed multiple cystic lesions in the anterior and posterior mediastinum. Surgery was carried out and histopathology and immunohistochemistry confirmed the diagnosis of multiple coelomic cysts of the mediastinum.

关键词： Mesothelial Cysts Mediastinum Surgery Pathology

Efficient Binary Tree Multiclass SVM Using Genetic Algorithms for Vowels Recognition

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通讯和计算机：中英文版 2012年第10期9卷 1116-1123页

作者： Boutkhil Sidaoui kaddour Sadouni Mlathematics and Computer Science Department University of Tahar Moulay Saida Saida 20000 Algeria Computer Science Department University of Sciences and Technology USTO-MB Oran 31000 Algeria

In this paper the authors introduce and investigate the performance of a simple framework for multiclass problems of SVM (support vector machine), the authors present a new architecture named EBTSVM (efficient binary tree multiclass SVM), in order to achieve high classification efficiency for multiclass problems. The proposed paradigm builds a binary tree for multiclass SVM by genetic algorithms with the aim of obtaining optimal partitions for the optimal tree. Our approach is more accurate in the construction of the tree. Further, in the test phase EBTSVM, due to its log complexity, it is much faster than other methods in problems that have big class number. In the context of phonetic classification by EBTSVM machine, a recognition rate of 57.54%, on the 20 vowels of TIMIT corpus was achieved. These results are comparable with the state of the arts, in particular the results obtained by SVM with one-versus-one strategy. In addition, training time and number of support vectors, which determine the duration of the tests, are also reduced compared to other methods. However, these results are unacceptably large for the speech recognition task. This calls for the development of more efficient multi-class kernel methods in terms of accuracy and sparsity.

关键词：元音识别遗传算法 SVM 二叉树支持向量机多类分类测试阶段训练时间

Synthesis of Amphiphilic Polyelectrolyte and Study of Their Association Behavior in Hydroalcoholic Media

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Journal of Chemistry and Chemical Engineering 2012年第6期6卷 574-583页

作者： Wahiba Chaibi kaddour Guemra Fatiha Bezzaoucha Physical and Organic Macromolecular Chemistry Laboratory Faculty of Science University "Djillali Liabes" of Sidi Bel-Abbes PB 89 Algeria

The objective of the work involves the synthesis of comb-like amphiphilic cationic polymers with repeating units methacylamides laterally substituted by a group containing a quaternary ammonium site and a hydrophobic n-alkyl side chain with 8-10 carbon atoms. Two synthesis methods were developed successfully. The first method is consisted to synthesizing first amphiphilic cationic methacrylamide monomers. In the second method the tertiary amine groups of polymers precursors were quaternised with various n-alkyl bromides. All the polymers obtained in this way were characterized by spectroscopic methods: 1H NMR and by viscometry. The reduced viscosity of hydro-alcoholic polymer solution decreases with polymer concentration. Viscometry study showed that these polymers display typical polysoap behavior in hydro-alcoholic mixtures.

关键词：聚合物电解质合成方法疏水性两亲性行为研究阳离子聚合物粘度测定法协会

Complicated Fusobacterium necrophorum mastoiditis–More than meets the eye

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Discussion of Clinical Cases 2019年第3期6卷 9-12页

作者： Katherine Fuller Mohamad kaddour Linny Phuong Joanna Lawrence Royal Children’s Hospital ParkvilleAustralia University of Melbourne ParkvilleAustralia

Otitis media is common in children and Fusobacterium species are an emerging causative *** species have virulence factors which increase the risk of complicated otitis *** discuss a case of *** infection resulting in significant intracranial disease to highlight the epidemiology of these infections,risk factors for complicated disease and signs and symptoms to guide diagnosis and investigation.

关键词： Otitis media Fusobacterium necrophorum Mastoiditis Osteomyelitis Lemierre’s syndrome Cavernous sinus thrombosis

Analytical Model for GaAs MESFET with High Pinchoff Voltage

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材料科学与工程（中英文A版） 2013年第12期3卷 853-858页

作者： Chahrazed kaddour Cherifa Azizi Saade Edine Khemissi Mourad Zaabat Yasemina Saidi Faculty of Exact Sciences Larbi Ben M'hidi University Oum El Bouaghi 04200 Algeria

GaAs MESFET gallium arsenide metal semiconductor field effect transistor play an important role in high speed electronic circuits because of their higher velocity and mobility characteristics. For that, we propose in this communication a static model for the transistor in thin layers on base of gallium arsenide. This model describes the characteristics current-voltages which are connected to the various physical and electric parameters of material. It is valid for the components which have the high pinchoff-voltage (Vp > 3 V). The theoretical results obtained were compared with those of the experiment.

关键词： MESFET器件夹断电压 GaAs 金属半导体场效应晶体管解析模型移动特性电子电路静态模型