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Resume Introduction L’administration des medicaments par sonde de nutrition enterale est une potentielle source de iatrogenie en raison du probleme de formes galeniques non adaptees. Objectifs Analyser les prescriptions des patients sous nutrition enterale afin de determiner si les formes galeniques prescrites etaient compatibles avec ce mode d’administration. Observer et evaluer les pratiques d’administration de ces medicaments par les infirmieres. Patients et methodes Nous avons prospectivement analyse 30 prescriptions de patients sous nutrition enterale par sonde gastrique dans le service de reanimation medicale de l’hopital universitaire Habib Bourguiba de Sfax. Nous avons observe et evalue les pratiques des infirmieres lors de la preparation et l’administration de medicaments a ces patients par sonde de nutrition enterale. Resultats Seuls 12 % des formes prescrites etaient liquides. Quatre-vingt-huit pour cent de ces medicaments ont ete broyes et les capsules ont ete ouvertes avant administration. Les formes galeniques etaient non conformes dans 22 % des cas (forme gastro-resistante pulverisee, administration de formes injectables avec risque d’irritation…). Sur les 78 medicaments administres par dix infirmiers differents, le temps entre le passage du medicament et celui de la nutrition enterale n’a pas ete respecte dans 56 % des observations, les medicaments ont ete melanges et administres en une seule fois dans 90 % des cas. Les gants ont ete portes dans 20 % des observations. Le rincage de la sonde n’a pas ete effectue entre des administrations consecutives ou avant chaque administration dans 100 % des observations. Conclusion Cette etude met en evidence le risque d’erreur lie a l’administration des medicaments par sonde de nutrition. La cooperation avec le pharmacien est necessaire afin de proposer des solutions par le choix de forme galenique adaptee ainsi que par la redaction de procedures d’administration.

Hydatid cysts are endemic in certain regions of the world. It can affect any organ. However, the primary site to the spermatic cord is an unusual location. Hydatid disease has been reported 5 times in the spermatic cord. The purpose of this study was to report a new case of a child with hydatid disease in the spermatic cord. This cyst is the first case treated successfully by Albendazole without surgery.Keywords: Echinococcal cyst; Spermatic cord; Albendazole; Surgery

In this paper, we consider a multiuser multiple input multiple output (MIMO) CDMA system where each user is transmitting different streams spread with the same code on a set of multiple antennas. Signals from one user are received as one group and each user is thought of as a virtual group. At the receiver, group ordered successive interference cancellation detection is applied. Optimal and sub-optimal group detection orders that maximizes the system performance are then derived. Various linear group detectors are considered such as the linear decorrelators and a closed form expression of the optimal order is given for the case of each of these group detectors. Numerical results demonstrate significant gains in the system performance as well as the importance of group ordering

In this paper, we investigate the use of layered space-time (also known as the vertical Bell Laboratories layered space-time (V-BLAST) scheme) for multiuser detection in fading channels. The multiple transmit antennas in V-BLAST are treated as individual mobile station transmitters, while the base station consists of multiple receive antennas. In the proposed system, users are organized in groups and allocated a unique spreading code within the same group. Using these codes, we are able to separate the different groups, and layered space-time algorithm is then invoked to further remove the remaining interference between users. A decorrelator-type receiver-based layered space-time detection is proposed for both complex and real constellations. For the latter case, we derive our receiver after evaluating and comparing the performance of two decorrelators based on the V-BLAST scheme. It is demonstrated that a significant performance improvement and increase in system capacity is obtained with very low spreading factors. Further results are also introduced by considering reduced complexity receivers based on serial layered space-time group multiuser detection, and parallel layered space-time group multiuser detection.

Background: The aim of the present study is to establish age- and sex-related reference ranges of serum IGF-I and IGF binding protein-3 (IGFBP-3) levels in a pattern of Tunisian children. Subjects and methods: Two hundred healthy Tunisian children (103 boys and 97 girls), aged between 6 and 16 yr, were considered in the study. Results: Mean serum levels of IGF-I and IGFBP-3 are observed to be higher in girls compared to boys of the same age interval. However, these differences were statistically significant only in pubertal ages (11–14 yr) for IGF-I and in pre-pubertal ages (6–10 yr) for IGFBP-3 (p

We consider a collaborative wireless distributed network, consisting of one source transmitting information to a remote destination in the presence of N relay nodes. We assume that all nodes have similar capabilities, are randomly distributed geographically, immersed in the clutter and close to the ground, each employing a single antenna. Assuming a Decode-and-Forward technique, we propose various collaborative approaches for signaling. Using well-known channel coding techniques, the destination is not able to start decoding its intended message until all nodes have decoded the entire message. Using more sophisticated coding techniques, the destination can start decoding the transmitted message at the start of the communication by the source. Various ways of organizing the relay collaboration are: Generalized Beamforming; Generalized Alamouti; and Simultaneous Casting. We then evaluate the performance of these collaborative approaches by simulations, employing an appropriate fading/path loss channel model. Obtained results will demonstrate the superiority of the sophisticated coding technique used and provide insights on when collaboration in networked multiple antennae systems is useful. Specifically, a gain of the order of 9 dB in the required transmit power is achieved assuming Simultaneous Casting and 0 dB transmit power per node, compared to the case when these sophisticated codes are not used. Finally, we also observe a gain in the system 10th percentile outage rate on the order of 1.4 bit/s/Hz at a 0 dB transmit power and with Generalized Beamforming, compared to the case where relays are not used.

In this paper we consider a system in which multiple dipole antennas are placed side-by-side within a finite space at the receiver to form a uniform linear array, causing the dipole antennas to be closely spaced. We investigate the achievable rate with receive antenna selection and take into account both spatial correlation and mutual coupling effects between the antennas. We assume the full channel state information is available at the receiver but not at the transmitter. Opposite to what might be expected, the system achievable rate with receive antenna selection can outperform the system employing all the antennas, provided the number of antennas used is larger than a critical value. We also describe the optimal processing scheme which enumerates all possible antenna combinations and selects the combination maximizing the instantaneous achievable rate for a given channel realization.

In this study we propose a new architecture named VIP (VHE in mobile IP networks) which guarantees authorized user access and user mobility management. The main goal is to bring the VIP architecture closer to the current GSM networks. To achieve this goal our architecture is based on LDAP and RADIUS services. VIP is able to ensure user's mobility across different IP domains. For the transportation of personalized services across different networks VHE (Virtual Home Environment) is employed. VHE gives a set of recommendations for providing users their home environment in foreign networks. The VHE services are activated to transport the user's profile between the home and the foreign network. Index Terms—VHE, Roaming, IEEE 802.11, Security

Mobility management is an important topic in wireless networks. Mobile hosts are subject to changing their point of attachment from his home network to another foreign network. In terms of personalized services, the network manager must know the user location by implementing a roaming mechanism. VHE (virtual home environment) provides to the users an identical computing network environment in a foreign network to the one in their home network. In this paper we propose an architecture that ensures authorized user access and user mobility management. This architecture also guarantees the management of personalized services of the user according to the VHE specifications. We introduce a new concept named "mobility service provider" (MSP) which manages user mobility. The mechanisms for user authentication, management and update of the user profile, are based on LDAP (lightweight directory access protocol) services. For authorized user access, RADIUS (remote access dial in user service) security services are used. Additionally to user authentication, the main goal is service adaptability regardless of the equipment utilized. The VHE services are able to convey the user's profile between the home and foreign network. We present in this paper an architecture that supports user mobility.

Summary form only given. VHE (virtual home environment) poses new challenges in terms of services customization and the integration of end-to-end QoS management. Our approach provides a model for the mobility management in IPv6 according to VHE context. In this paper we introduce an architecture which guarantees authorized user access and user mobility management. The mechanism used for user authentication is based on LDAP (lightweight directory access protocol) and RADIUS (remote access dial in user service) services, giving accurate localization of the mobile node even in the presence of hadover; at this point, the user must be re-authenticated and consequently the VHE services are activated to transport the user profile to the foreign network.

In this paper, we propose an improved pre-combining group detection in the presence of improper multi-access interference (MAI). We consider a transmission of K BPSK signals over M diversity channels in rich scattering environments. The different received signals are grouped at the receiver, and detected jointly in groups using maximum likelihood (ML) detection. The novelty of the proposed scheme consists in the proper use of the information contained in the MAI statistical properties. We show that the proposed receiver achieves higher diversity order gains than conventional group detectors. For example, a gain of the order of |G~|/2 is obtained for the group G compared with the conventional receiver, where |G~| is the interferers number. Particularly, when the group size is one, the proposed receiver is equivalent to a decorrelator that can null out (K-1) interferers while providing a diversity order of (M- (K-1/2) for each signal. Exact pairwise-error probability along with bounds for the bit-error rate are derived for each group. Numerical results will also show that optimum performance is closely approached when the proposed architecture is used.

We propose in this paper a novel group detection scheme that we denote by group ordered successive interference cancellation (GOSIC) multiuser detector. We consider a multiuser MIMO CDMA communication system, where each user carries more than one antenna, but is assigned only one spreading signature. Users are then considered as virtual groups. Our proposed receiver consists of ordering these users at the receiver side in order to maximize the overall system performance, and carrying group detection for each one using layered space-time processing. We define and derive the optimal user order based on the group signal to noise ratio (GSNR), and show that not only it is optimal in this sense but also in the sense of asymptotic symmetric energy. We also propose another sub-optimal order in order to overcome the complexity issues. Finally, we compare the performance of our proposed receivers with traditional group serial interference cancellation and conventional layered space-time multiuser architectures, and show that significant improvement is introduced.

This paper assesses the impact of layered space-time multiuser detection (LAST-MUD) in wireless circuit switched and packet switched modes integrated CDMA systems. The network is hence composed of packet and circuit radio mobile stations transmitting to an antenna array at the base station receiver. These users are organized in different groups and users in a particular group are allocated the same spreading code. Therefore, the CDMA spreading technique will remove the interference between the groups and the layered space-time scheme will further remove the remaining interference between users. The effect of packet mode users on system performance is considered. Throughput and BER performances of packet and circuit mode users are hence investigated, respectively. The robustness of the LAST-MUD is also demonstrated against transmission power variation of packet mode users.

The upcoming 3/sup rd/ telecommunication telephony generation is setting forth a new set of challenges in the development and deployment of numerous telecom services which follow the requirements and expectations of end-users. This paper describes our approach to provide the user with an environment to set up his own preferences when using such multimedia telecom services. Our purpose is to keep services, profiles and behaviors unchanged and just compose them in a safe way in purpose to generate added value services that answer to the end user expectations. The first implementation is provided and tested on Web applications where we integrate the user profiles with no modification on the XML document. In particular we describe how we adapt the representation according to the end-user requirements. Then we extend our approach to a more flexible system. Our purpose was to provide an environment for end-user QoS control of multimedia telecom services that integrate behavior as well as profiles. We also present our evaluation of the approach that has been realized and the future study.

In this paper, we investigate the use of layered space-time scheme, known as V-BLAST, for multiuser detection over the uplink of a DS/CDMA communication system. The multiple transmit antennas in V-BLAST are treated as individual mobile station transmitters, while the base station consists of multiple receive antennas. The layered space-time algorithm is then invoked to detect the signals from all users. In addition, CDMA is also applied. Groups of users are arranged and allocated the same signature sequence or spreading code. The groups of users are first separated using the group spreading codes, and the layered space-time detection algorithm is then invoked to further remove the remaining interference. It is demonstrated that a significant performance improvement and increase in system capacity are obtained with very low spreading factors.

We assess the impact of layered space-time detection technique, known as V-BLAST, for multiuser detection over a packetized random access system based on CDMA and slotted Aloha. In this scheme, the multiple transmit antennas are treated as individual packet radio mobile stations, while the base station consists of multiple receive antennas. In addition, users are arranged in groups and allocated the same group signature sequence. The spreading technique is hence used to separate between the groups, and the layered space-time algorithm is then invoked to detect the signals from all users transmitting packets at the same time. A significant improvement in system throughput, delay and capacity are achieved.

ALOHA systems are some of the most attractive options for wireless applications which include packet transmission. However, despite their flexibility and simplicity, they present a very low channel throughput. The objective of this paper is to analyze the performance of such a protocol based layered space-time scheme over wireless communication links. A multiuser environment is hence considered in which each user carries only one transmit antenna. A generalization of Vertical-Layered Space-Time (V-BLAST) technique for BPSK modulation is then invoked to detect the transmitted signals through the use of multiple receive antennas at the base station. We asses in this paper the gain achieved by the proposed receiver; denoted by rT-BLAST, compared to the conventional V-BLAST system. We first consider the performance of this system over flat fading channels for a variety of system parameters. Then, throughput and delay performance are analyzed under different packetized traffics. It is demonstrated through simulation results that a significant improvement in system capacity, throughput and delay are achieved.