Ahmed M.J.,University of Baghdad
Ecological Engineering | Year: 2017
Phragmites australis (PS) or common reed is one of the best-known herbaceous crops whose industrial potential is now being intensively reconsidered. The high yield and low input requirements make it a promising source for chemicals and biofuels. Besides, many studies have discussed its great potential as a renewable precursor with unique chemical composition for preparation of activated carbons (ACs) with high-grades. Thus, this article provided an overview of the different studies that used raw and activated PS as adsorbents for treatment of synthetic dyes and heavy metals. Adsorption isotherms, kinetics, and mechanisms of these pollutants were also reviewed. According to collected data, maximum Langmuir capacities of 58.82 and 33.0 mg/g were reported for dyes and metals on raw PS, compared to 526.32 and 53.71 mg/g on activated PS, respectively. ACs from PS biomass showed excellent performance for wastewater treatment, thus solving environmental problems of waste disposal and pollution control. © 2017 Elsevier B.V.
Lafta R.,University of Baghdad
The Lancet | Year: 2013
After decades of war, sanctions, and occupation, Iraq's health services are struggling to regain lost momentum. Many skilled health workers have moved to other countries, and young graduates continue to leave. In spite of much rebuilding, health infrastructure is not fully restored. National development plans call for a realignment of the health system with primary health care as the basis. Yet the health-care system continues to be centralised and focused on hospitals. These development plans also call for the introduction of private health care as a major force in the health sector, but much needs to be done before policies to support this change are in place. New initiatives include an active programme to match access to health services with the location and needs of the population.
Hapangama D.K.,University of Liverpool |
Kamal A.M.,University of Baghdad |
Bulmer J.N.,Northumbria University
Human reproduction update | Year: 2015
BACKGROUND: The endometrium is the primary target organ for the 'female' sex steroid hormone estrogen, which exerts effects in the endometrium via two main classical estrogen receptor (ER) isoforms, ERα and ERβ. The main function of the endometrium, embryo implantation, appears unperturbed in ERβ knockout mice, which has led researchers to disregard other potentially important functional roles that ERβ may have in endometrium. This review focuses on ERβ in the human endometrium and its protective role from the undesired effects of ERα.METHODS: We conducted a systematic search using PubMed and Ovid for publications between January 1996 and February 2014. All studies that examined ERβ expression or function in non-pregnant endometrium or cells derived from the endometrium were considered, including human and animal studies.RESULTS: Studies of the basic function of ERβ isoforms in restraining ERα-mediated cell-specific trophic/mitotic responses to estrogen in other tissues has allowed appreciation of the important potential role of ERβ in the regulation of cell fate in the human endometrium. Our current understanding of ERβ expression and function in endometrium is, however, incomplete. ERβ is dynamically expressed in healthy premenstrual endometrium, persists in post-menopausal atrophic endometrium and may play an important role in endometrial disease. All endometrial cell types express ERβ and aberrations in ERβ expression have been reported in almost all benign and malignant endometrial proliferative disease.CONCLUSIONS: The collective evidence suggests that ERβ has an important role in normal endometrial function and also in most, if not all, benign and malignant endometrial diseases. However, the conduct of studies of endometrial ERβ expression needs to be standardized: agreement is needed regarding the most appropriate control tissue for endometrial cancer studies as well as development of standardized methods for the quantification of ERβ immunohistochemical data, similar to those scoring systems employed for other hormonally regulated tissues such as breast cancer, since these data may have direct clinical implications in guiding therapy. © The Author 2014. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: email@example.com.
Al-Ameri T.K.,University of Baghdad
Marine and Petroleum Geology | Year: 2011
This work presents new insights of the generation, quality and migration pathways of the hydrocarbons in the East Baghdad Oil Field.The Khasib and Tannuma formations in East Baghdad are considered as oil reservoirs according to their high porosity (15-23%) and permeability (20-45 mD) in carbonate rocks. The hydrocarbons are trapped by structural anticline closure trending NW-SE. Gas chromatography analysis on these oil reservoirshave shown biomarkers of abundant ranges of n-alkanes of less than C22 (C17-C21) with C19 and C18 peaks. This suggests mainly liquid oil constituents of paraffinic hydrocarbons from marine algal source of restricted palaeoenvironments in the reservoir. The low non aromatic C15 + peaks are indicative for slight degradation and water washing. Oil biomarkers of Pr./Ph. = 0.85, C31/C30 < 1.0, location in triangle of C27-C29 sterane, C28/C29 of 0.6 sterane, Oleanane of 0.01 and CPI = 1.0, indicate an anoxic marine environment with carbonate deposits of Upper Jurassic to Early Cretaceous age. Four Miospores, seven Dinoflagellates and one Tasmanite species confirm affinity to the upper most Jurassic to Lower Cretaceous Chia Gara and Ratawi Formations.The recorded palynomorphs from the Khasib and Tannuma Formations are of light brown color of TAI = 2.8-3.0 and comparable to the mature palynomorphs that belong to the Chia Gara and the Lower part of Ratawi Formations.The Chia Gara Formation generated oil during Upper Cretaceous to Early Palaeogene and accumulated in structural traps of Cretaceous age, such as the Khasib and Tannuma reservoirs. The Chia Gara Formation generated and expelled high quantities of oil hydrocarbons according to their TOC wt% of 0.5-8.5 with S2 = 2.5-18.5 mg Hc/g Rock, high hydrogen index of the range 150-450 mg Hc/g Rock, good petroleum potential of 4.5-23.5 mg Hc/g Rock, mature (TAI = 2.8-3.0 and Tmax = 428-443C), kerogen type II and palynofacies parameters of up to 100% AOM (Amorphous Organic Matters). This includes algae deposits in a dysoxic-anoxic to suboxic-anoxic environment.Alternative plays are discussed according to the migration pathways. © 2010 Elsevier Ltd.
Alwan S.M.,University of Baghdad
Molecules | Year: 2012
New derivatives of 7-aminocephalosporanic acid 1-8 were synthesized by acylation of the 7-amino group of the cephem nucleus with various arylidinimino-1,3,4- thiadiazole-thio(or dithio)-acetic acid intermediates 3a-d and 5a-d, respectively, so the acyl side chains of these new cephalosporins contained a sulfide or disulfide bond. This unique combination of a Schiff base with the sulfide or disulfide bonds in the acyl side chain afforded new cephalosporins of reasonable potencies, some of which were found to possess moderate activities against the tested microorganisms. Their chemical structures were characterized by H-NMR, IR spectroscopy and elemental microanalysis. Preliminary in vitro antimicrobial activities of the prepared cephalosporins were investigated using a panel of selected microorganisms. Results indicated that the newly synthesized cephalosporins containing disulfide bonds (compounds 5-8) exhibited better activities against Staphylococcus aureus and Escherichia coli. The cephalosporins cross-linked by a sulfide bond (compounds 1-4) showed a slight change in antimicrobial activities when compared with that of the reference cephalosporin (cephalexin). © 2012 by the authors.
Amori K.E.,University of Baghdad |
Abd-AlRaheem M.A.,University of Baghdad
Renewable Energy | Year: 2014
In the present work a comparative study for thermal and electrical performance of different hybrid photovoltaic/thermal collectors designs for Iraq climate conditions have been carried out. Four different types of air based hybrid PV/T collectors have been manufactured and tested. Three collectors consist of four main parts namely, channel duct, glass cover, axial fan to circulate air and two PV panels in parallel connection. The measured parameters are, the temperature of the upper and the lower surfaces of the PV panels, air temperature along the collector, air flow rate, pressure drop, power produced by solar cell, and climate conditions such as wind speed, solar radiation and ambient temperature. The thermal and hydraulic performances of PV/T collector model IV have been analyzed theoretically based on energy balance. A Matlab computer program has been developed to solve the proposed mathematical model.The obtained results show that the combined efficiency of collector model III (double duct, single pass) is higher than that of model II (single duct double pass) and model IV (single duct single pass). Model IV has the better electrical efficiency. The pressure drop of model III is lower than that of models II and IV. The root mean square of percentage deviations for PV outlet temperature, and thermal efficiency of model IV are found to be 3.22%, and 18.04% respectively. The calculated linear coefficients of correlation ( r) are 0.977, 0.965 respectively. © 2013 Elsevier Ltd.
Attea B.A.,University of Baghdad |
Khalil E.A.,University of Baghdad
Applied Soft Computing Journal | Year: 2012
Wireless sensor network (WSN) is a rapidly evolving technological platform with tremendous and novel applications. Recent advances in WSN have led to many new protocols specifically designed for them where energy awareness (i.e. long lived wireless network) is an essential consideration. Most of the attention, however, has been given to the routing protocols since they might differ depending on the application and network architecture. As routing approach with hierarchical structure is realized to successfully provide energy efficient solution, various heuristic clustering algorithms have been proposed. As an attractive WSN routing protocol, LEACH has been widely accepted for its energy efficiency and simplicity. Also, the discipline of meta-heuristics Evolutionary Algorithms (EAs) has been utilized by several researchers to tackle cluster-based routing problem in WSN. These biologically inspired routing mechanisms, e.g., HCR, have proved beneficial in prolonging the WSN lifetime, but unfortunately at the expense of decreasing the stability period of WSN. This is most probably due to the abstract modeling of the EA's clustering fitness function. The aim of this paper is to alleviate the undesirable behavior of the EA when dealing with clustered routing problem in WSN by formulating a new fitness function that incorporates two clustering aspects, viz. cohesion and separation error. Simulation over 20 random heterogeneous WSNs shows that our evolutionary based clustered routing protocol (ERP) always prolongs the network lifetime, preserves more energy as compared to the results obtained using the current heuristics such as LEACH, SEP, and HCR protocols. Additionally, we found that ERP outperforms LEACH and HCR in prolonging the stability period, comparable to SEP performance for heterogeneous networks with 10% extra heterogeneity but requires further heterogeneous-aware modification in the presence of 20% of node heterogeneity. © 2011 Elsevier B.V. All rights reserved.
Hammadi O.A.,University of Baghdad
Photonic Sensors | Year: 2015
In this work, the photovoltaic properties of selenium-doped silicon photodiodes were studied. Influence of illumination of the impurity absorption range on the current-voltage and spectral characteristics of the fabricated device were considered. The photoresponse dependencies on the electric intensity, current, and radiation power at the sample were observed. Results obtained in this work showed that the current-sensitivity of the fabricated structures at the forward bias was rather higher than that of photoresistors. The photosensitivity and detectivity were up to 2.85×10−16W·Hz−1/2 and 2.1×1011cm·Hz1/2W−1, respectively. © 2015, The Author(s).
Amori K.E.,University of Baghdad |
Taqi Al-Najjar H.M.,University of Baghdad
Applied Energy | Year: 2012
The electrical and thermal performance of a typical single pass hybrid photovoltaic/thermal (PV/T) air collector is modeled, simulated and analyzed for two selected case studies in Iraq. An improved mathematical thermo-electrical model is derived in terms of design, operating and climatic parameters of the hybrid solar collector to evaluate its important characteristics: collector flow and heat removal factors, PV maximum power point and its temperature coefficient, and overall power and efficiency. Unlike previous PV/T thermal models, the present model is obtained with some additions and corrections in radiation and convection heat coefficients for the top loss and for the air duct with more applicable sky temperature correlation. The well-known 5-parameter electrical model of PV module is solved using improved boundary conditions and translation equations for better convergence and accuracy. The voltage temperature coefficient of the PV module is included in the boundary conditions for convergence stability. The module parameters are taken to be dependent on solar radiation and PV cell temperature for improved accuracy. A Matlab computer simulation program is developed to solve the thermo-electrical model. The developed model is verified with previously published experimental results and theoretical simulations; it is proved to be most accurate in respect to percentage errors and correlation coefficients. Different parameters of the PV/T collector such as cell and air temperatures, thermal gain, PV current and voltage, and fill factor have been investigated. The results identified the effects of most important operating conditions such as sky, inlet and cell temperatures, air flow rate and incident solar radiation on the performance of the hybrid collector. The approved model is applied for a winter day (22 January 2011) in Baghdad city and for a summer day (20 May 2011) in Fallujah city. It is found that the electrical, thermal and overall collector efficiencies for the two case studies were 12.3%, 19.4% and 53.6% respectively for the winter day, while that for the summer day were 9%, 22.8% and 47.8%. © 2012 Elsevier Ltd.
Hasan Z.N.,University of Baghdad
Southern Medical Journal | Year: 2011
Background: Stroke is one of the major causes of morbidity and mortality throughout the world. Reports about the role of Chlamydia pneumoniae infection in the development of atherosclerosis have been reported in many studies. The aim of the study was to evaluate the association between Chlamydia pneumoniae infection and ischemic stroke. Methods: We evaluated 50 patients with ischemic stroke (32 males and 18 females) and 40 control subjects (22 males and 18 females). They were age- and sex-matched. All enrolled subjects underwent an enzyme-linked immunosorbent assay (ELISA) serologic test for IgG and IgA antibodies for Chlamydia pneumoniae. Results: Eighteen (36%) patients with ischemic stroke have positive IgA, in comparison with 6 (15%) among the control group (OR 3.18; CI 1.12-9.04; P = 0.03). This translates into the fact that there was a more than three-fold risk of developing ischemic stroke in those with Chlamydia pneumoniae infection compared to those who without. The IgG seropositivity was increased in patients with ischemic stroke, but it did not reach statistical significance (OR = 2.32; CI = 0.97-5.58; P = 0.078). Conclusions: Chronic Chlamydia pneumoniae infection demonstrated by positive IgA-type antibody can be considered a significant risk for ischemic stroke. Copyright © 2011 by The Southern Medical Association.