University of Dohuk

Dihok, Iraq

University of Dohuk

Dihok, Iraq
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Ilyas B.M.,University Of Dohuk | Elias B.H.,University of Dohuk
Physica B: Condensed Matter | Year: 2017

The structural, elastic, electronic, optical acoustic and thermodynamic properties of the cubic perovskite CsPbCl3 and CsCdCl3 unit cell, were studied using an ultra-soft pseudopotential plane wave, the Trouiller-Martins-Functional was utilized to perform these calculations. The study was implemented within both the Local Density Approximation (LDA) and the Generalized Gradient Approximation (GGA). the Generalized Gradient Approximation (GGA) scheme proposed by van Leeuwen-Baerends which is the same as the Perdew-Wang 92 functional have been carried out to preform our calculations. As for the Local Density Approximation (LDA) the Teter-Pade parametrization (4/93) was implemented which is the same as Perdew-Wang that in its turn reproduces the Ceperley-Alder-Functional. The computed GGA/LDA-lattice parameter for both CsCdCl3 and CsPbCl3 is in an exquisite agreement with the experimental and theoretical results. The energy band structure shows that CsCdCl3 is Γ–R indirect band gap insulator, while CsPbCl3 is an insulator with a direct band gap Γ–Γ separating the valence bands from the conduction bands, which shows metallic nature after pressure 30 GPa. A hybridization exists between Pb-p states and Cl-p states for CsPbCl3, and Cd-p states and Cs-p states for the CsCdCl3 in the valence bonding region. Optimization of both cell shape (geometry) volume were investigated as pressure of 0–20 GPa and 0–40 GPa for the CsCdCl3 and CsPbCl3 respectively. The Pressure dependence of cubic perovskite elastic constants, Young modulus, bulk and shear moduli, Lame's constants, elastic anisotropy factor, elastic wave velocities, phonon dispersion, Debye temperature and the density of states of CsXCl3 (X=Pb, Cd) were theoretically calculated and compared with the other available theoretical results. The above elastic constants reveal the fact that both compounds are stable and show nature of ductility. For the optical properties, both the static refractive index and dielectric constant are found to be related proportionally to the indirect band gap of CsCdCl3. The refractive index, extinction coefficient, complex dielectric function, energy loss function, optical conductivity, reflectivity and absorption coefficient for 0–25 eV incident photon energies have been predicted. The phonon properties were investigated using response functions to predict the phonon lattice dispersion and the density of states. The thermal effect on the heat capacities, entropy, enthalpy and Free energy were predicted and compared using both the quasi-harmonic Debye model and response functions, the latter provided far better results. To the best of the authors' knowledge, most of the studied properties have not been experimentally reported so far. Generally, the computed results for both CsCdCl3 and CsPbCl3 are very satisfactory and show good agreement with other calculations. © 2017 Elsevier B.V.

Ali I.,University of Dohuk | Moiron S.,VMware | Fleury M.,University of Essex | Ghanbari M.,University of Essex | Ghanbari M.,Sharif University of Technology
IEEE Wireless Communications | Year: 2013

Multiple description video coding can exploit path diversity to improve error resiliency by generating several independently decodable video descriptions and sending them over different paths. Such paths are readily available in ad hoc wireless networks. To approach the original quality, all descriptions need to be successfully received. However, in a wireless channel, error bursts or link disruption may still affect one or more descriptions, resulting in significant drops in video quality. This article describes a lower complexity yet effective scheme for video streaming over such wireless networks. In order to improve error resiliency, the scheme combines unequal packet importance with the advantages of path diversity. The scheme can be implemented with a minimal increase in computational complexity, as spatial decomposition of video frames is employed to generate the descriptions. Experimental results for an ad hoc wireless network show that a significant objective quality gain can be achieved (up to 3 dB) in the presence of signal shadow fading. © 2013 IEEE.

Hamamy H.,University of Geneva | Makrythanasis P.,University of Geneva | Al-Allawi N.,University of Dohuk | Muhsin A.A.,Hematology Oncology unit | Antonarakis S.E.,University of Geneva
BMC Medical Genetics | Year: 2014

Background: Inherited thrombocytopenias (IT) are a heterogeneous group of rare diseases characterized by a reduced number of blood platelets. The frequency of IT is probably underestimated because of diagnostic difficulties and because not all the existing forms have as yet been identified, with some patients remaining without a definitive diagnosis. Exome Sequencing has made possible the identification of almost all variants in the coding regions of protein-coding genes, thereby providing the opportunity to identify the disease causing gene in a number of patients with indefinite diagnoses, specifically in consanguineous families. Case presentation: Familial thrombocytopenia with small size platelets was present in several members of a highly consanguineous family from Northern Iraq. Genotyping of all affected, their unaffected siblings and parents, followed by exome sequencing revealed a strong candidate loss of function variant in a homozygous state: a frameshift mutation in the gene. The protein encoded by this gene is known to be a cytosolic adaptor molecule expressed by T, natural killer (NK), myeloid cells and platelets, and is involved in platelet activation and controls the expression of interleukin-2. Knock-out mice were reported to show isolated thrombocytopenia. Conclusion: Inherited thrombocytopenias differ in their presentation, associated features, and molecular etiologies. An accurate diagnosis is needed to provide appropriate management as well as counseling for the individuals and their family members. Exome sequencing may become a first diagnostic tool to identify the molecular basis of undiagnosed familial IT. In this report, the clinical evaluation combined with the power and efficiency of genomic analysis defined the FYB gene as the possible underlying cause of autosomal recessive thrombocytopenia with small platelet size. This is the first report linking pathogenic variants in FYB and thrombocytopenia in humans. © Hamamy et al.

Al-Allawi N.A.S.,University of Dohuk | Al-Mousawi B.M.S.,University of Baghdad | Badi A.I.A.,University of Dohuk | Jalal S.D.,Sulaimaniyah University
Hemoglobin | Year: 2013

While previous studies from Iraq have focused on β-thalassemia (β-thal) mutations in the northern part of the country, inhabited mainly by Kurds, no study of significance has looked at these mutations in central or southern Iraq, which is inhabited by the Arab majority. For the latter purpose this study was initiated and 103 β-thal carriers from Baghdad at the center of the country were investigated using multiplex polymerase chain reaction (PCR) and reverse hybridization followed by sequencing. The results revealed that a total of 17 mutations were implicated, six of which, IVS-I-110 (G>A), IVS-II-1 (G>A), IVS-I-5 (G>C), codons 8/9 (+G), IVS-I-I (G>A) and codon 44 (-C), constituted 78.0% of the mutations characterized. Among the 17 mutations identified, six are reported for the first time from Iraq and include: IVS-I, 25 bp deletion, IVS-II-848 (C>A), -28 (A>C), IVS-I-130 (G>C), IVS-I-128 (T>G) and codons 41/42 (-TTCT). The findings of the current study clearly illustrate the genetic heterogeneity of the population of central Iraq, as demonstrated by the presence of a combination of Mediterranean, Asian Indian, Kurdish, Iranian, Egyptian, Saudi Arabian and Turkish mutations that is reflective of the historical background of this part of the country. Copyright © Informa Healthcare USA, Inc.

Al-Allawi N.A.,University of Dohuk | Ismaeel A.T.,Hawler Medical University | Ahmed N.Y.,Hawler Medical University | Merza N.S.,University of Dohuk
Indian Journal of Cancer | Year: 2012

Background: The epidemiology of colorectal cancers (CRC) is well known to differ in different geographical regions. K-ras mutations have been implicated in CRC carcinogenesis and they were extensively studied in developed countries; however, such studies are scarce from developing countries, like Iraq. Aim: To determine the frequency and spectrum of K-ras mutations among CRC Iraqi patients, and their clinico-pathological associations, if any. Materials and Methods: Fifty consecutive surgically resected sporadic CRC were evaluated. The evaluation included screening for ten K-ras mutations in codon 12 and 13 by mutant enriched polymerase chain reaction followed by reverse hybridization to oligospecific probes. Results: Out of the 50 enrolled patients, 24 (48%) had K-ras mutations. A total of 29 mutations were identified in the tumors of the latter 24 patients (20/24 tumors had single mutations, 3/24 had double mutations and 1/24 had triple mutations). The most frequently encountered mutations were the G>T transversions and G>A transitions (41.4% each). Codon 12 mutations constituted 89.7%, while codon 13 the remaining 10.3%. The most frequent mutation was GGT>GTT (Gly>Val) of codon 12 documented in 31%. No significant clinico-pathological correlations with K-ras mutational status were identified. Conclusion:The K-ras mutations are frequently encountered among Iraqi sporadic CRC patients, with relative higher frequencies of G>T transversions and Gly>Val codon 12 substitutions than encountered in their counterparts in developed countries. The latter is most likely to be related to differences in local carcinogens exposure, an aspect which requires further scrutiny.

Sheet M.H.,University of Dohuk
ARPN Journal of Engineering and Applied Sciences | Year: 2012

This paper focused on studying the effect of silt quantity in soils on the performance of synthetic fabrics called Geotextiles, which is a standard set by the U.S. Army Corps of Engineers to evaluate the degree of fabric clogging. Certain hydraulic relationships were established to determine the effect of silt quantity in soils on the performance of Geotextiles. From the results we found out a relation between silt quantity and gradient ratio, so the increase of silt quantity in soils leads to increase gradient ratio and that causes increase clogging degree of the synthetic fabric (Geotextile). © 2006-2012 Asian Research Publishing Network (ARPN).

Yaqo R.T.,University of Dohuk | Hughson M.D.,Shorash Hospital | Sulayvani F.K.,University of Dohuk | Al-Allawi N.A.,University of Dohuk
Indian Journal of Cancer | Year: 2011

Background: Based on the World Health Organization (WHO) classification, the distribution of various subtypes of malignant lymphoma (ML) appears to differ by geographical region. Aims and Design: studying the patterns of ML retrospectively in a previously uncharted country (Iraq) and to compare it with patterns observed regionally and worldwide. Materials and Methods: Two hundred and seventy lymphoma patients referred to two major histopathology referral centers in Northern Iraq, were categorized according to the WHO classification, using morphology and appropriate immunohistochemistry. Results: There were 205 (76%) non-Hodgkin lymphomas (NHL) and 65 (24%) Hodgkin lymphomas (HL). Of the NHL, 91% were B-cell and 9% T-cell. The most common NHL was Diffuse large B-cell lymphoma (DLBCL) which comprised 52.2% of NHL, followed by Burkitt's lymphoma (BL) at 14.6%. The latter were mostly intestinal primaries. While follicular lymphomas (FL) were infrequent constituting 2.9 % of NHL. Extranodal primaries were found in 48.3% of NHL. Hodgkin's lymphoma (HL) included 48% nodular sclerosis (NS) and 37% mixed cellularity (MC). All HL were nodal primaries. Conclusions: Among NHL, the high frequencies of DLBCL, extra nodal primaries and intestinal BL, and the infrequency of FL in northern Iraq, is similar to reports from nearby countries but differs considerably from the West and Far East, indicating a shared regional Middle East influence on non-Hodgkin lymphoma patterns. In contrast to earlier Iraqi and regional studies on HL, NS has surpassed MC as the most frequent histological subtype in Northern Iraq. This trend probably reflects the increasing urbanization that has taken place in this region.

Memon A.A.,University of Nottingham | Memon A.A.,Health Science University | Hussein N.R.,University of Nottingham | Hussein N.R.,University of Dohuk | And 3 more authors.
Journal of Clinical Microbiology | Year: 2014

The Helicobacter pylori virulence gene, cagA, and active forms of the vacuolating cytotoxin gene, vacA, are major determinants of pathogenesis. However, previous studies linking these factors to disease risk have often included patients using aspirin/nonsteroidal anti-inflammatory agents (NSAIDs) or acid-suppressing drugs, both of which may confound results. Also, particularly for gastric cancer (GC), controls have often been of quite different ages. Here, we performed a careful study in a "clean" Belgian population with gastric cancer cases age and sex matched to 4 controls and with a parallel duodenal ulcer (DU) group. As in other populations, there was a close association between the presence of cagA and the vacA s1 genotype. For GC, associations were found for vacA s1-positive (P=0.01, odds ratio [OR], 9.37; 95% confidence interval [CI], 1.16 to 201.89), i1-positive (P=0.003; OR, 12.08; 95% CI, 1.50 to 259.64), and cagA-positive status (P<0.05; OR, infinity; 95% CI, 0.76 to infinity). For DU, associations were found with vacA s1 (P=0.002; OR, 6.04; 95% CI, 1.52 to 27.87) and i1 (P=0.004; OR, 4.35; 95% CI, 1.36 to 14.78) status but not with cagA status. Neither condition showed independent associations with the vacA m1 allele or with more biologically active forms of cagA with longer 3′ variable regions. In this Belgian population, the best markers of gastric cancer- and duodenal ulcer-associated strains are the vacA s1 and i1 genotypes. This fits with experimental data showing that the s and i regions are the key determinants of vacuolating cytotoxin activity. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

β-thalassaemia major and sickle-cell disease are important health problems in Iraq. To provide information for a prevention programme, the frequency of haemoglobin disorders was mapped in Dohuk governorate. A total of 591 couples (1182 individuals) attending health centres for premarital health screening were tested; 44 (3.7%) were found to be carriers of β-thalassaemia, 14 (1.2%) of the sickle-cell gene and 1 (0.1%) of δβ-thalassaemia. A total of 3 couples (i.e. 5/1000) were at risk of having a child with β-thalassaemia major, and the estimated number of affected children with a major haemoglobinopathy was 39 per year. The findings stress the importance of a regional prevention programme for haemoglobinopathies based on premarital screening, counselling and prenatal diagnosis.

Al-Allawi N.A.,University of Dohuk
Annals of Saudi medicine | Year: 2010

Hemoglobin Barts hydrops fetalis syndrome is the most severe and generally fatal clinical phenotype of alpha-thalassemia. We diagnosed a fetus at 23-weeks gestation with having hydrops fetalis, by ultrasound. At 32 weeks, intrauterine death was detected. Molecular studies revealed that the fetus had the hemoglobin Barts hydrops fetalis syndrome due to homozygosity for the Mediterranean alpha-thalassemia deletion. This clinical phenotype is generally rare in the Eastern Mediterranean, and this is the first report of this syndrome from Iraq. Techniques for molecular characterization became available only very recently in this country, in a diagnostic setting. Thus, the detection of further cases might be expected in future.

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