Design of a Broadband Amplifier for High Speed Applications

This paper provides comprehensive insight into the design approach followed for an amplifier dedicated to high speed base band signals. To demonstrate the methodology, an amplifier consisting of nine PHEMT cascode cells within a distributed amplifier topology was designed. The resulting frequency response is 40 GHz at the 3-dB point, and the output voltage for a 43 Gbps eye diagram is 7.3 Vpp at the chip terminal

Histological exploration of follicular population of the Moroccan bovine (Oulmes-Zaers) breed

Follicular population and repartition in the ovarian cortex was investigated in the ovaries of the Oulmès-Zaers cattle breed and its crosses. A total of 30 ovaries were collected at slaughterhouse in Casablanca and Rabat from Oulmes-Zaers breed and its crosses (2 genotypes) of 3 age groups (5 years). The histological study of the ovary revealed that the ovarian cortex is composed of different areas (from the periphery to the medulla), the non stratified epithelium of the ovary, the tunica albuginea composed of two areas rich of collagen fibers directed into different ways white variable thickness. The primordial and antral follicles appear in underlying areas. Therefore, the follicles cannot appear on the ovarian surface when situated under thicker Layers. At the quantitative level, the ovary of the Oulmes-Zaears breed seems to contain less follicles in animals less than 3 years of age as compared to the crossbreed (P< 0.05). Between 3 and 5 years of age, the follicles occupied similar areas of the ovaries (17% and 18% for oulmes-Zaers and its crosses, respectively). This study shows that the ovary of the Moroccan local cattle breed (Oulmes-Zaers) is equipped with a whole plain follicular population that is more important than the one visible on the surface of the ovary and which is exploited by aspiration and picking techniques. Key words: Ovary, Oulmès-Zaers, follicular population, bovine, age. African Journal of Biotechnology Vol.3(5) 2004: 294-29

Prise en charge des complications des fistules artério-veineuses pour hémodialyse chronique

La fistule artério-veineuse native est l'accès vasculaire de choix pour  l'hémodialyse chronique en raison de sa longévité, son taux faible de complication et de mortalité par rapport aux pontages artério-veineux et aux cathéters. Cependant, il arrive assez souvent que l'on assiste à des complications qui sont dominées par la sténose et la thrombose. C'est une étude rétrospective des complications ayants survenues pour 31 fistules artério-veineuses pour hémodialyse chronique des 200 fistules réalisées chez 200 patients au sein du service de chirurgie vasculaire du CHU Hassan II de Fès sur une période de trois ans, étendue de Janvier 2007 à  Décembre 2009. Ces complications ont été présentés par les thrombosesdans 14 cas soit 45,15% de l'ensemble des complications, les sténoses dans 4 cas (12,90%,) les anévrismes dans 4 cas (12,90%), les  complications ischémiques dans 3 cas (9,67%), l'infection dans 3 cas (9,67%), l'hémorragie dans 2 cas (6,45%) et l' hyperdébit dans un seul cas soit 3,22%. On a pu conserver 22 fistules soit 70,96% par traitement chirurgical ou endovasculaire, on a confectionné une nouvelle fistule dans 8cas soit 25,80%, et on a adressé une patiente (3,22%) pour pose d'un cathéter veineux tunnelisé permanent. Les complications des fistules artério-veineuses pour l'hémodialyse chronique sont la principale cause de morbidité chez les patients hémodialysés, il est donc important de s'impliquer lors de leur création, et de donner un maximum d'attention quand ils sont manipulés. Ceci suggère la mise en place d'un programme de surveillance de ces fistules en raison de l'impact des complications sur la morbi-mortalité du patient hémodialysé et sur le plan financier

Genetic and nongenetic effects on the number of ovarian follicles and oocyte yield and quality in the bovine local (Oulmes Zaer), exotic breeds and their crosses in Morocco

The effects of genetic and non genetic factors on the number of ovarian follicles and oocyte yield and quality in the bovine local breed (Oulmes Zaer), exotic breeds and their crosses in Morocco was investigated. In this study, females in very bad body conditions (BCS < 2) were not slaughtered and the average. The body condition scores (BCS) was 2.94 ± 0.89. Although some individual values were out of the normal ranges, mean values of total proteins, albumin, urea, &#946;-OH and GOT remain normal and were 77.83 ± 8.74 g/l, 32.4 ± 4.41g/l, 4.43 ± 2.13 mmol/l , 0.83± 0.48 mmol/l et 45.55 ± 11.95 UI/l, respectively. The mean number of ovarian follicles per cow (2-8 mm) was high (22.98 ± 8.41) whereas the oocyte yield (and 2.60 ± 1.53) was very low. The effects of genetic group, age and BCS on the number of follicles, oocyte yield and the quality were significant. Key Words: Cows, follicular population, oocyte yield and quality. African Journal of Biotechnology Vol.4(1) 2005: 9-1

Stuctural And Magnetic Characterization Of CoxZn1-x/Cu Multilayers Obtained by Electrodeposition

We present the experimental results of (CoxZn1-x/Cu)n multilayers (3<x<10) grown using the electrochemical dual bath method. The X-ray diffraction patterns have shown that the CoZn structural lattice parameters are close to those of the monoclinic CoZn13 compound. We have developed an analytical model in the X-ray kinematical theory adapted to the electrodeposited (CoxZn1-x/Cu) multilayers. We have shown that the model can give interesting structural information about the multilayer components, and reproduces the position of the satellite peaks around the main diffraction peak. Thus we have deduced the multilayer period and performed comparison between experimental results and the analytical model. The magnetic properties at room temperature reveal both superparamagnetic and ferromagnetic features. The inclusion of Zn into the magnetic layer and the existence of CoZnCu based alloy at the interfacial regions explain the magnetic properties. The magnetoresistance (MR) loop displays a broad , rounded maximum and the saturation is not observed even at high applied fields. The MR(H) behaviour and its small ratio can be attributed to interfacial effects.We present the experimental results of (CoxZn1-x/Cu)n multilayers (3<x<10) grown using the electrochemical dual bath method. The X-ray diffraction patterns have shown that the CoZn structural lattice parameters are close to those of the monoclinic CoZn13 compound. We have developed an analytical model in the X-ray kinematical theory adapted to the electrodeposited (CoxZn1-x/Cu) multilayers. We have shown that the model can give interesting structural information about the multilayer components, and reproduces the position of the satellite peaks around the main diffraction peak. Thus we have deduced the multilayer period and performed comparison between experimental results and the analytical model. The magnetic properties at room temperature reveal both superparamagnetic and ferromagnetic features. The inclusion of Zn into the magnetic layer and the existence of CoZnCu based alloy at the interfacial regions explain the magnetic properties. The magnetoresistance (MR) loop displays a broad , rounded maximum and the saturation is not observed even at high applied fields. The MR(H) behaviour and its small ratio can be attributed to interfacial effects