Redesigning the Schedule Time Slots for Qatar University to Cope with Local Specificities

This study is concerned with the redesign of the class meeting pattern at Qatar University. It examines the existing meeting pattern based on its operational efficiency, its alignment with the strategic plan of the University, and its perception by the students and the faculty members. The analysis reveals serious limitations and shows the need for a new pattern with a full non-teaching day and no one-hour lectures. A capacity analysis proves the feasibility of such a pattern. Taking into consideration the specifications of the Qatari society, it was judged that the non-teaching day be split in two-half days. The present research recognizes the distinction between scheduling and class meeting patterns and aims to address the under-researched theme of having the meeting pattern as a variable rather than just an input to scheduling

White noise Heisenberg evolution and Evans-Hudson flows

We study white noise Heisenberg equations giving rise to flows which are *-automorphisms of the observable algebra, but not necessarily inner automorphisms. We prove that the causally normally ordered form of these white noise Heisenberg equations are equivalent to Evans–Hudson flows. This gives in particular, the microscopic structure of the maps defining these flows, in terms of the original white noise derivations

Chemokine and Chemokine Receptor Gene Polymorphism in Tunisian Hemodialysis Patients with HCV Infection

Introduction: Our aim was to investigate the possibility of a significant relationship between chemokines and chemokine receptor genes polymorphisms and the spontaneous clearance or the persistence of HCV infection. Methods: A total of 96 hemodialysis (HD) patients infected with HCV were classified into two groups: G1 included 73 patients with persistently positive HCV-RNA and G2 included 23 HD patients who have spontaneously eliminated the virus. The control group consisted of 170 healthy blood donors. All subjects were genotyped for CCR5 Δ32, CCR5 (-59029) A/G, CCR2 (64Ile) and MCP-1(-2518) A/G gene polymorphisms. Results: Our results showed statistically significant increased frequencies of the CCR2 (64Ile) and the (-59029) CCR5 A alleles in patients infected with HCV (22.1% and 35.9%) compared to G1 (24.3% and 40.6%) and compared to controls (14.4% and 20%). We also observed a lower frequency of the MCP-1 G allele and a greater frequency of the CCR5Δ32 variant in G2 (15.2% and 6.5%) compared to G1 (22.6% and 1.4%) that was not statistically significant. However, adjustment for known covariates (age, gender and HCV genotypes) didn’t confirm the results of univariate analysis. Conclusion: In conclusion, our study suggests a possible role for some of the studied chemokines polymorphisms in the spontaneous clearance or persistence of HCV infection in Tunisian population. These results should be further investigated by a prospective cohort studies and large population-based studies.Keywords: Chemokines; Receptors; Hepatitis C virus; Spontaneous Clearance; Polymorphisms

Genetic variation of durum wheat landraces using morphological and protein markers

Genetic variations of cultivars are very interesting in reducing genetic vulnerability and lead to stable control of production. The aim of this research was to study genetic diversity among six durum wheat cultivars. For the first assay we evaluated seven morphological traits which are: spikelet per spike, spike length, spike width, beard length, plant height, width of truncation and barb length. The tested genotypes were classified in three groups according to the linkage distance analysis. The genetic variability was also evaluated for seed storage-proteins by sodium dodecylsulphate polyacrylamide gel electrophoresis (SDS-PAGE). Electrophoregram allowed the estimation of the durum wheat genetic similarity (GS). This GS analysis based on Unweighted Pair Group Method with Arithmetic averages (UPGMA), permits to obtain the same genotypic clustering. No significant correlation was observed among the two methods tested. It is concluded that seed storage protein profiles could be useful markers in the studies of genetic diversity and genotypes classification, which can be used to improve the efficiency of wheat breeding programs.Key words: Wheat genotypes, SDS-PAGE, genetic diversity, cluster analysis

Lupus érythémateux systémique à début pédiatrique: à propos d’un cas

Le lupus érythémateux systémique (LES) est une maladie systémique auto-immune d'étiologie inconnue qui touche essentiellement les femmes àl'âge adulte. Le lupus pédiatrique est une entité rare. Nous rapportons une nouvelle observation. Il s'agissait d'un nourrisson âgé de 7 mois quiprésentait des lésions cutanées purpuriques, une polyarthrite fébrile. Le bilan immunologique était positif (AAN et anti-ADN). Une améliorationclinique et biologique a été notée sous corticothérapie générale avec une récidive lors de la dégression du traitement

Effects of rubber aggregates on the physical-mechanical, thermal and durability properties of self-compacting sand concrete

The aim of this research was to study the effect of incorporating waste rubber aggregates on the physical, mechanical, thermal and durability performance of Self-Compacting Sand Concrete SCSC mixtures. For this purpose, the separately developed Rubberized Self-Compacting Sand Concrete RSCSC were prepared with three fractions of rubber grains where the natural aggregates were replaced with powder rubber, sand rubber and gravel rubber and four addition ratios (5, 10, 15 and 20%) as volume rates. The performed fresh properties using slump-flow, spreading, t500, sieve stability and air-entrained content tests proved better results for the RSCSC in comparison with reference concretes. Hardened state characterization of the concretes exhibited decreases in the mechanical properties of the RSCSC but the thermal conductivity and the dynamic elastic modulus were improved. Assessment of the concrete’s durability was accomplished through determination of apparent porosity, capillary absorption. Therefore, RSCSC to be can used in structural elements of dense reinforcement and complex formwork. Furthermore, this allows promising solution to reduce the impact of waste tyres on the environment and fight pollution

Characterization of in-situ Doped Polycrystalline Silicon Using Schottky Diodes and Admittance Spectroscopy

In this work, Schottky Au-Polycrystalline silicon diodes are successfully realised. The barrier height is around ФB = 0.74 eV as determined from Capacitance – Bias (C-V) characteristics. The depth profile of the apparent doping is deduced from these measurements. Its behaviour leads to the experimental profile. Moreover, the diode admittance measurements versus the frequency and the temperature at different biases show the possibility to use this device to characterise the electrical quality of the polycrystalline silicon