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Journal of Life Sciences 2015年第10期9卷 465-471页

作者： Jomaa Chemkhi Souheila Guerbouj Ikram Guizani afif ben salah Laboratoire d'Epidemiologie Moleculaire et Pathologie Experimentale Appliquee aux Maladies infectieuses (LRl lIPT04) InstitutPasteur de Tunis Universite Tunis El Manar Tunisia Laboratoire d'Epidemiologie Medicale Institut Pasteur de Tunis Universite Tunis El Manar Tunisia

Phlebotomine sandflies （Diptera： Psychodidae） constitute a large group of flies, many of which have been described as vectors of leishmaniasis, a disease caused by Leishmania （Kinetoplastida： Trypanosomatidae） parasites. In Tunisia, a total of 17 species belonging to both genera Phlebotomus and Sergentomyia were described. In this work we report on an abnormality found in spermathecae of a female specimen ofPhlebotomus （Larroussius） longicuspis Nitzulescu, 1930. Sandflies were collected in SidiSaad locality, in the govemorate of Kairouan, central Tunisia, where zoonotic cutaneous leishmaniasis is endemic, during the June to November 2011 period, using CDC light traps. Males were washed and directly identified and females were dissected and morphologically identified using the head and the last two abdominal segments containing spermathecae and ducts. 162 flies were morphologically described. Among 33 females identified as Phlebotomus （Larroussius） longicuspis, one specimen was found abnormal and presented with three spermathecae. An additional spermathecae located in a short bifurcation on the upper extremity of one duct was found. This anomaly is for the first time described in Tunisia. Morphological abnormalities are important to report in order to avoid erroneous sandfly identification or description of new species.

关键词： Phlebotomine sand fly spermathecae anomaly.

THE LERAY-SCHAUDER CONDITION FOR 1-SET WEAKLY-CONTRACTIVE AND(ws)-COMPACT OPERATORS

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Acta Mathematica Scientia 2014年第2期34卷 263-273页

作者： afif ben AMAR Department of Mathematics Faculty of Sciences

Abstract The main purpose of this article is to prove a collection of new nxea point theorems for （ws）-compact and so-called 1-set weakly contractive operators under Leray- Schauder boundary condition. We also introduce the concept of semi-closed operator at the origin and obtain a series of new fixed point theorems for such class of operators. As consequences, we get new fixed point existence for （ws）-compact （in particular nonexpansive） self mappings unbounded closed convex subset of Banach spaces. The main condition in our results is formulated in terms of axiomatic measures of weak noncompactness. Later on, we give an application to generalized Hammerstein type integral equations.

关键词： Measure of weak noncompactness weakly condensing and weakly nonexpan-sire (ws)-compact operator fixed point theorems semi-closed at the origin

MEASURES OF WEAK NONCOMPACTNESS AND FIXED POINT THEORY FOR 1-SET WEAKLY CONTRACTIVE OPERATORS ON UNBOUNDED DOMAINS

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Analysis in Theory and Applications 2011年第3期27卷 224-238页

作者： ShaoyuanXu afif ben Amar Department of Mathematics and Information TechnologyHanshan Normal UniversityChaozhou 521041 Departement de MathematiquesUniversite de Gafsa Cite Universitaire Zarrouk Faculte des Sciences de Gafsa2112 Gafsa Tunisie

The main purpose of this paper is to prove a collection of new fixed point theorems and existence theorems for the nonlinear operator equation F（x） = αx （α≥〉 1） for so-called 1-set weakly contractive operators on unbounded domains in Banach spaces. We also introduce the concept of weakly semi-closed operator at the origin and obtain a series of new fixed point theorems and the existence theorems for the nonlinear operator equation F（x） = αx （α≥1） for such class of operators. As consequences, the main results general- ize and improve the relevant results, which are obtained by O＇Regan and A. ben Amar and M. Mnif in 1998 and 2009 respectively. In addition, we get the famous fixed point theorems of Leray-Schauder, Altman, Petryshyn and Rothe type in the case of weakly sequentially continuous, 1-set weakly contractive （μ-nonexpansive） and weakly semi-closed operators at the origin and their generalizations. The main condition in our results is formulated in terms of axiomatic measures of weak compactness.

关键词： measure of weak noncompactness weakly condensing and weakly nonexpansive weakly sequentially continuous weakly semi-closed at the origin fixedpoint theorem

无界域上1-集弱压缩算子的新不动点结果(英文)

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应用数学 2013年第2期26卷 268-276页

作者：许绍元 afif ben Amar 韩山师范学院数学与应用数学系广东潮州521041 Département de Mathématiques Université de GafsaCité Universitaire Zarrouk

本文证明Banach空间中无界域上一类弱序列连续和1-集弱压缩算子的若干新不动点定理.我们引入原点处弱半闭算子,得到该算子的若干不动点定理.进而将著名的Leray-Schauder不动点定理、Altman定理、Roth定理和Petryshyn定理推广到弱序列连... 详细信息

本文证明Banach空间中无界域上一类弱序列连续和1-集弱压缩算子的若干新不动点定理.我们引入原点处弱半闭算子,得到该算子的若干不动点定理.进而将著名的Leray-Schauder不动点定理、Altman定理、Roth定理和Petryshyn定理推广到弱序列连续算子和1-集弱压缩算子以及原点处弱半闭算子的情形.本文的主要结果依赖于非紧性弱原子测度的有关条件.

关键词：非紧性测度弱凝聚和弱非扩张弱序列连续在原点弱半闭不动点定理

Fixed Point Theory for 1-Set Weakly Contractive Operators in Banach Spaces

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Analysis in Theory and Applications 2013年第3期29卷 208-220页

作者： Shaoyuan Xu afif ben Amar Department of Mathematics and Statistics Hanshan Normal University De'partement de Mathe'matiques Faculte' des Sciences de SfaxUniversite' de SfaxSfaxTunisia

In this work, using an analogue of Sadovskii＇s fixed point result and several important inequalities we investigate and give new existence theorems for the nonlinear operator equation F（x） =μx, （μ≥1） for some weakly sequentially continuous, weakly condensing and weakly 1-set weakly contractive operators with different boundary conditions. Correspondingly, we can obtain some applicable fixed point theorems of Leray-Schauder, Altman and Furi-Pera types in the weak topology setting which generalize and improve the corresponding results of [3,15,16].

关键词： Weakly condensing weakly sequentially continuous fixed point theorem operator equation.

On Some Fixed Point Theorems for 1-Set Weakly Contractive Multi-Valued Mappings with Weakly Sequentially Closed Graph

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Advances in Pure Mathematics 2011年第4期1卷 163-169页

作者： afif ben Amar Aneta Sikorska-Nowak 不详

In this paper we prove Leray-Schauder and Furi-Pera types fixed point theorems for a class of multi-valued mappings with weakly sequentially closed graph. Our results improve and extend previous results for weakly sequentially closed maps and are very important in applications, mainly for the investigating of boundary value problems on noncompact intervals.

关键词： Measures of Weak Noncompactness Weakly Condensing Weakly Nonexpansive

Distributed Relay Diversity Systems for OFDM-Based Networks

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International Journal of Communications, Network and System Sciences 2008年第3期1卷 215-227页

作者： afif OSSEIRAN Andrew LOGOTHETIS Slimane ben SLIMANE Airspan Networks previously with Ericsson Research Ericsson Research Stockholm Sweden Royal Institute of Technology (KTH) Stockholm Sweden

In this paper, distributed relay diversity systems are analyzed, modeled and evaluated in an Orthogonal Frequency Division Multiplexing (OFDM) based networks. The investigated distributed relay diversity schemes extend the ideas of a single hop transmit antenna schemes such as Cyclic Delay Diversity (CDD), Space Time Transmit Diversity (STTD), transmit Coherent Combining (CC) and Selection Diversity (SD) to distributed diversity systems. In contrast to the classical single hop system, the antennas in the distributed systems belongs to distributed relays instead of being co-located at the transmitter. The distributed relay diversity methods considered in this paper: Relay CDD (RCDD), Relay Alamouti (***), Relay CC (RCC) and Relay SD (RSD) are compared to the traditional 1-hop system. Analytical expressions for the received Signal to Interference Noise Ratio (SINR) are derived and used in a dynamic multi-cell multi-user simulator. Results show considerable SINR gains for both Round Robin and Max-SINR schedulers. The SINR gains translate into substantial cell throughput gains, up to 200%, compared to 1-hop systems. Despite its low complexity, the RCDD scheme has similar performance to that of other more sophisticated 2-hop schemes such as Relay Alamouti and Relay Coherent Combining. Marginally better results are observed for the Relay Selection Diversity scheme.

关键词： Coherent Combining Cooperative Communication Cyclic Delay Diversity Multi-User Diversity OFDM Relay Node Selection Diversity Space Time Transmit Diversity System Performance

Children Flat Foot and Lower Limb Rotational Profile: A Cross-Sectional Descriptive Study

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Open Journal of Orthopedics 2015年第10期5卷 326-335页

作者： Jemni Sonia Lazreg Nadia Abid Manel Frioui Samia ben Rejeb Mohamed Osman Walid Zaoui afif Khachnaoui Faycel Department of Physical Therapy and Rehabilitation Sahloul Hospital Sousse Tunisia High School of Sciences and Technology of Health of Sousse Sousse Tunisia Community and Preventive Medicine Department Sahloul Hospital Sousse Tunisia Orthopedic Department Sahloul Hospital Sousse Tunisia

Flat foot in children is a common deformation, which appears during the first years of life. It requires a rigorous evaluation to rule out congenital or neurological abnormality. It is characterized by a decrease of the plantar concavity indeed collapse of the foot, often associated with other morphostatic deformations. The aim of this study is to find a correlation between the essential flat foot in children and lower limb disorders torsional. It is a cross-sectional descriptive study, recruiting 110 children (220 feet) aged between 3 and 6 years old. Each child was given an assessment of the morphology of the foot (Contact Index II…) and lower limb rotational profile (intoeing and femoral antétorsion and tibal torsion). Among 110 children, 21 (19.1%) have bilateral flat feet and 7 (6.4%) have unilateral flat feet, associated with an average value of Contact Index II equal to 0.921;the minimum value is 0.880 and the maximum value is 1.17. All children with flat feet have excessive femoral antétorsion;45 (92%) are associated with a hip intoeing and 38 (80%) present an insufficient external tibial torsion. The analysis of multiple regression shows a significantly elevated correlation among the flat foot and excessive internal rotation of the hip (F = 70.36, r = 0.77, P < 0.001), excessive femoral antetorsion (F = 54.78, r = 0.73, P < 0.001) and insufficient external tibial torsion (F = 7.79, r = 0.37, P < 0.001).

关键词： Children Essential Flat Foot Femoral Antétorsion Internal Rotation of the Hip Tibial Torsion