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Search Results: 1 - 10 of 170688 matches for " Omar H. Al-Obaidi "
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Synthesis, Characterization and Antimicrobial Screening Mixed-Ligand Cu(II) and Zn(II) Complexes; DNA Binding Studies on Cu(II) Complex  [PDF]
Omar H. Al-Obaidi
Open Journal of Inorganic Non-metallic Materials (OJINM) , 2012, DOI: 10.4236/ojinm.2012.24007
Abstract: Several mixed ligand Cu(II), Zn(II) complexes using (benzylidenethiourea) (obtained by the condensation of benzaldehyde and thiourea) as the primary ligand and (acetamide or thioacetamide) as an additional ligand were synthesized and characterized analytically and spectroscopically, magnetic susceptibility and molar conductance measurements ,as well as by UV-Vis. and IR spectroscopy. The interaction of the complexes with calf thymus (CT)DNA was studied using absorption spectra, while the concentration of DNA in gel electrophoresis remained constant at 10 μl. They exhibit absorption hypochromicity increased during the binding of the complexes to calf thymus DNA. The complexes show enhanced antimicrobial activities complexes with the free ligand. A theoretical treatment of the formation of complexes in the gas phase was studied, this was done using the HYPERCHEM-6 program for the Molecular mechanics and Semi-empirical calculations.
Binuclear Cu(II) and Co(II) Complexes of Tridentate Heterocyclic Shiff Base Derived from Salicylaldehyde with 4-Aminoantipyrine
Omar Hamad Shihab Al-Obaidi
Bioinorganic Chemistry and Applications , 2012, DOI: 10.1155/2012/601879
Abstract: New binuclear Co(II) and Co(II) complexes of ONO tridentate heterocyclic Schiff base derived from 4-aminoantipyrine with salicylaldehyde have been synthesized and characterized on the bases of elemental analysis, UV-Vis., FT-IR, and also by aid of molar conductivity measurements, magnetic measurements, and melting points. It has been found that the Schiff bases with Cu(II) or Co(II) ion forming binuclear complexes on (1?:?1) “metal : ligand” stoichiometry. The molar conductance measurements of the complexes in DMSO correspond to be nonelectrolytic nature for all prepared complexes. Distorted octahedral environment is suggested for metal complexes. A theoretical treatment of the formation of complexes in the gas phase was studied, and this was done by using the HyperChem-6 program for the molecular mechanics and semi-empirical calculations. The free ligand and its complexes have been tested for their antibacterial activities against two types of human pathogenic bacteria: the first type (Staphylococcus aureus) is Gram positive and the second type (Escherichia coli) is Gram negative (by using agar well diffusion method). Finally, it was found that compounds show different activity of inhibition on growth of the bacteria. 1. Introduction Amino heterocyclic compounds containing two or more potential donor centers play an important role in the study of competitive reactivity of an bidentate ligand system [1]. Heterocyclic phenazone and their derivatives (4-aminoantipyrine) are known to act as bidentate or tridentate ligands when coordinated to metal ion [2]. Phenazone ligand can form mononuclear and binuclear complexes [3–5]. Transition metal complexes containing a salicylaldehyde are commonly found in biological media and play important roles in processes such as catalysis of drug interaction with biomolecules [6]. Phenazone Schiff base chemistry is less extensive, and our laboratory has been exploring this chemistry [7–10]. In this paper we are reporting the synthesis of the binuclear Co(II) and Cu(II) complexes of some heterocyclic Schiff base ligands (Figure 1) containing 4-aminoantipyrine. Spectral and magnetic studies have been used to characterize the structure of the complexes. Figure 1: Structure of the ligands L1 and L2. 2. Experimental 2.1. Physical Measurements A Fisher-100 infrared spectrophotometer was used to record the IR spectra as KBr and CsI disc, and UV/VIS spectra were measured by a HITACHI U-2000 spectrophotometer. Determination of all metals percentage by atomic absorption spectrophotometry on AA-680G (Shimadzu). Electrical conductance
New Bioactive Molecules with Potential Antioxidant Activity from Various Extracts of Wild Edible Gelam Mushroom (Boletus spp.)  [PDF]
M. H. M. Y. Yuswan, Jameel R. Al-Obaidi, A. Rahayu, S. Sahidan, F. Shazrul, D. Fauzi
Advances in Bioscience and Biotechnology (ABB) , 2015, DOI: 10.4236/abb.2015.64031
Abstract: Boletus spp. is a wild edible Gelam mushroom, which is only available at coastal area of Bachok, Kelantan. Locals have used this mushroom as a food source and as a traditional medicine. In this study, antioxidants were extracted using Mili-Q water and methanol. Extraction of 1.0 g of Boletus spp. mushroom pileus and stipe by water produced 0.22 ± 0.09 g and 0.3 ± 0.07 g of total aqueous soluble extracts, respectively. Methanol extraction of 1.0 g Boletus spp. mushroom pileus and stipe produced 0.31 ± 0.08 mg and 0.37 ± 0.05 mg of total methanol soluble extracts, respectively. DPPH assay has been used to determine the value of antioxidant efficiency of each extracts. DPPH assay revealed that the EC50 value of pileus aqueous soluble extract and both pileus and stipe methanol soluble extracts were 1.2 mg/ml. The EC50 value of stipe aqueous soluble extracts was 1.4 mg/ml. The EC50 value of ascorbic acid, an antioxidant control was 0.5 mg/ml. Liquid chromatography- DPPH (LC-DPPH) assay combined with Quadrupole Time-of-flight Mass Spectrometry (QTOF-MS) analysis of 3:2 ratio methanol and water extract has detected 43 antioxidant compounds that were involved in the reduction of DPPH. To identify these compounds, SIMCA 3.0 software that consists of PCA, OPLS-DA and s-plot analyses had been used. PCA analysis had shown the antioxidant activity from sample on DPPH as 73.6%. This antioxidant activity confirmed by OPLS-DA analysis had shown the variability between sample and control as 99.6% with 99.3% prediction. S-plot selection had shown ten antioxidant compounds significantly involved in the DPPH assay. Four of these compounds were identified by the METLIN and NIST databases. The antioxidant metabolites were 2,4,6-trimethylacetophenone imine, glutamyl tryptophan, azatadine and lithocholic acid glycine conjugate. In conclusion, this study revealed that Boletus spp. mushroom is rich with natural antioxidants, which are potentially useful for multiple nutritional and health applications.
Changes in some biochemical parameters accompanied with Brucellosis in native goats
S. H. Arslan,N. A. Al-Hussary,Q. T. Al-Obaidi,M. M. Hassan
Iraqi Journal of Veterinary Sciences , 2011,
Abstract: The aim of the study was to determine changes in some of biochemical parameters accompanied with brucellosis naturally infected native goats. The study included examination of 102 blood sera representing 396 native goats from different areas in Mosul city using rose bengal test, indirect ELISA test and tube agglutination test. Results showed that prevalence of brucellosis by using rose bengal test and indirect ELISA test was (6.8% and 24.5%) respectively. Titers of rose bengal seropostive sera ranged (1/80 -1/640), whereas titers of indirect ELISA seropostive sera ranged (1/40 - 1/640) using tube agglutination test. Results also showed significant increase in aspartate transaminase, alanine transaminase, lactate dehydrogenase and significant increased in alkaline phosphatase, there were also significant increases in glucose concentration, total and direct bilirubin, triglycerides and cholesterol, whereas total protein and albumin values were significantly decreased. All these parameters examinated on seropostive sera for indirect ELISA and tube agglutination tests in goats naturally infected with brucellosis compared with seronegative sera for same tests.
A comparative study between Rose Bengal and indirect ELISA tests for detection of the antibrucella antibodies in serum of goats in Mosul city
S. H. Arslan,Q. T. Al-Obaidi,M. A. Al-Taliby,S. D. Hassan
Iraqi Journal of Veterinary Sciences , 2010,
Abstract: This study was conducted to determine seroprevalence of brucellosis in non vaccinated goats in different areas in Mosulcity and to compare Rose Bengal and indirect ELISA tests for the detection of the antibodies. A total of 102 blood serumsamples were examined, representing 396 goats distributed in different areas. Results of Rose Bengal test showed that the totalseroprevalence of brucellosis was (6.8%) and the highest rate in Al-Rahmania (11.1%), and lowest (7.1%) in Al-Muthana area.No seroprevalence of Brucellosis was recorded in Googjaly and Basheka areas. Indirect ELISA test showed that the totalpercentage was (24.5%) and the highest (55%) were reported in Al-Rahmania area and the lowest percentage was (10%) inBasheka area. The compatibility between the two tests was (0.30) on Kappa value indicating sensitivity of indirect ELISA testcompared with Rose Bengal test in detection antibrucella antibodies in serum goats.
Prevalence of brucellosis using indirect ELISA test in raw milk in individual cases of ewes and does in Mosul city
Q. T. Al-Obaidi,S. D. Hassan,B. A. Mohammad,S. H. Arslan
Iraqi Journal of Veterinary Sciences , 2009,
Abstract: The aim of the study was to find the prevalence of brucellosis antibodies in individual cases of ewes and goats (3-8 weeks after parturition) using indirect ELISA test in raw milk in different areas of Mosul, and using Rose Bengal test in serum samples of same flocks of sheep and goats. Examination of 211 raw milk samples represented (1906) sheep and examination of 88 raw milk samples represented 102 goats randomly collected from individual cases. The study included examination of blood sera of 211 sheep and 88 goats. The prevalence of milk samples in ewes and does positive to antibodies of brucellosis was 6.6% and 11.3%, respectively. Highest percentage was in Al-hamdania area (20%), and lowest in Googjaly area (3.3%), but non recorded in Basheka, Bazwaya and shrazad areas. Examination of raw milk of does showed the highest percentage (22%) was in Al- Namrood area, and lowest (5%) in Hay-Alarabi area. Results of Rose Bengal test in serum samples of ewes and does were 8.5% and 5.8%, respectively. It is concluded that ELISA test on raw milk in individual cases can be considered a confirmatory screening test the with the Rose Bengal test in diagnosis of brucellosis in parturated ewes and does.
Clinical, haematological and biochemical studies of babesiosis in native goats in Mosul
E. G. Sulaiman,S. H. Arslan,Q. T. Al-Obaidi,E. Daham
Iraqi Journal of Veterinary Sciences , 2010,
Abstract: The study included examination of 175 native goats, 27 were infected with Babesia ovis, B. motasi, B. foliata and B. taylori, (recorded in Mosul for the first time) and 25 were clinically normal and served as control. Results indicated that the percentage of the infection with Babesiosis was 15.42% and the percentage of parasitemia ranged between 3.5-10.4% with a mean 6.95%, infected goats showed signs of loss of appetite, weakness, pale mucous membranes, jaundice, fever, coughing, nasal discharge, recumbency, diarrhea and haemoglobinuria. A statistically significant decrease were recorded in total red blood cells (RBC), haemoglobin concentration (Hb), packed cell volume (PCV) and platelets counts. Anemia was of microcytic hypochromic type. A statistically significant increase in erythrocyte sedimentation rate and significant increase in total white blood cells was recorded due to significant increase in lymphocyte and neutrophile count. Results of the biochemical testes indicated an increase in activity of alanin amino transferase (AST), aspartate amino transferase (ALT), total bilirubin, blood urea nitrogen and icterus index, with a significant decrease in total serum protein, albumin and globulin levels. Results also indicated the presence of Rhipecephalus ticks which were: Rh. sanguineus and Rh. turanicus.
Which Bit Is Better in Least Significant Bit?  [PDF]
Fatin E. M. Al-Obaidi, Ali Jassim Mohamed Ali
Journal of Information Security (JIS) , 2015, DOI: 10.4236/jis.2015.63017
Abstract: The weakness of Human Auditory System (HAS) led the audio steganography process to be used in hiding data in the digital sound. Audio steganography is implemented here by using Least Significant Bit (LSB) algorithm to hide message into multiple audio files. This is achieved by 1st, 2nd, 3rd, and 4th bits hiding ratios. In comparison to other used bits, hiding results show that the use of 1st bit in LSB method for embedding data is much better than those used bits as expected. In addition to that and according to the results, file’s size affects strongly upon the effectiveness of the embedding process while hiding starting position doesn’t affect upon the variation of the adopted statistical estimators regardless to which bit is used. Among the statistical estimators that have been adopted here, the Mean Absolute Error (MAE) seems to be the best one in testing hiding process.
Quality, Chemical and Microbial Characteristics of Table Eggs at Retail Stores in Baghdad
Faris A. Al-Obaidi,Shahrazad M.J. Al-Shadeedi,Rashed H. Al-Dalawi
International Journal of Poultry Science , 2011,
Abstract: The objective of this study was to determine the shelf life of marketed table eggs in some retail stores of Baghdad city through determination some quality, chemical and microbial characteristics of the eggs. A total of 1680 chicken eggs (10 eggs were locally produced and 10 eggs were imported) were collected biweekly from retail stores in different seven popular regions of Baghdad city during the period from January 14th to July 15th of 2010. The data obtained revealed that locally produced eggs had lower egg weight, albumen weight and albumen height and higher albumen and yolk pH compared with imported, also Psychrophilic, Coliform, Staphylococci and Fungi counts were high in locally produced eggs compared with imported. No significant differences between locally and imported eggs chemical composition except moisture which was significantly (p<0.05) higher in imported eggs. The total percentage of the incidence of Salmonella in table eggs at retail stores in Baghdad were 20.0% and 38.7% for locally and imported eggs respectively. This survey showed that marketed table eggs in retail stores of Baghdad city were of good quality and within the Iraq standard specification for eggs and where fit for consumption as shell eggs.
A multithreaded scheduling model for solving the Tower of Hanoi game in a multicore environment
Alaa M. Al-Obaidi
Maejo International Journal of Science and Technology , 2012,
Abstract: Modern computer systems greatly depend on multithreaded scheduling tobalance the workload among their working units. One of the multithreaded scheduling techniques, the work-stealing technique has proven effective in balancing the distribution of threads by stealing threads from the working cores and reallocating them to the nonworking cores. In this study, we propose a new strategy that extends the work-stealing technique by enabling it to select the richest core prior to any redistribution process. Inorder to obtain practical results, we applied this new strategy of balancing threads to one of the divide-and-conquer problems, the Tower of Hanoi game. A multithreaded scheduling model which is a hierarchical model was designed to work under the control of this new strategy. A modelling tool was used to simulate and verify the designed model. The proposed model was shown by the simulation process to exhibit consistency and stabilityin reaching the desired result. Scalability, concurrency, simplicity and fair load distribution among the modelled cores are the main beneficial characteristics of this model.
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