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Search Results: 1 - 10 of 403431 matches for " Abbas M. Hammam "
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Synthesis and thermal studies of mixed ligand complexes of Cu(II), Co(II), Ni(II) and Cd(II) with mercaptotriazoles and dehydroacetic acid  [PDF]
Dina M. Fouad, Ahmed Bayoumi, Mohamed A. ElGahami, Said A. Ibrahim, Abbas M. Hammam
Natural Science (NS) , 2010, DOI: 10.4236/ns.2010.28103
Abstract: A series of new mixed ligand complexes of cobalt(II), nickel(II), copper(II) and cadmium(II) have been synthesized with 3benzyl1H4[(2 methoxybenzylidine) amino]1, 2, 4triazole5 thione (MBT), 3bezyl1H4[(4chlorobenzylidine) amino]1, 2, 4triazole5thione (CBT), 3benzyl 1H4[(4nitrobenzylidine)amino]1, 2, 4triazole 5thione (NBT) and dehydroacetic acid sodium salt (Nadha). The mixed ligand complexes have been characterized by elemental analysis, spec troscopic spectral measurements (IR, UVVis.), molar conductance, magnetic measurements and thermal studies. The stoichiometry of these com plexes is M:L1:L2 = 1:1:1, 1:2:1 or 1:1:2 where L1 = NBT, CBT and MBT and L2 = Nadha. Tetrahedral structure was proposed for all Cd(II) mixed ligand complexes while the square planar geometry was proposed for Cu(II) mixed ligand complex with NBT. Octahedral structure was proposed for Ni(II), Co(II) mixed ligand complexes and Cu(II) mixed ligand complexes with CBT and MBT ligands. The thermal decomposition study of the prepared complexes was monitored by TG, DTG and DTA analysis in dynamic nitrogen atmosphere. TG, DTG and DTA studies confirmed the chemical formulations of theses complexes. The kinetic parameters were determined from the the thermal decomposition data using the graphical methods of CoatsRedfern and HorwitzMetzger. Thermodynamic parameters were calculated using standard relations.
The Toxicological effects of fenitrothion and vitamin E as antioxidant agent on the biochemical, cytogenetic and histopathological parameters of white rats
Fouad Abdel Reheim* Awad Abbas Ragab * Fatma.M. Hammam
Egyptian Journal of Hospital Medicine , 2008,
Abstract: Background: The use of pesticides has been increased considerably nowadays compared to the past. The hazards of using such chemical compounds have been accentuated by the sharp rise of their use in agriculture, industry, by householders and governments. Exposure to organophosphorus insecticides (OPI) in agriculture is one of the occupational hazards. Fenitrothion is one of the most important OPI. The major object of the present study was to evaluated the toxicological (biochemical, mutagenic and histopathological) effects of tested insecticide "fenitrothion" alone or combined to vitamin E as an antioxidant agent to decrease their toxic effect. Material and Method male albino rats were tested orally for 30 days, three doses of fenitrothion were used in absence and presence of vitamin E (1/20, 1/40 and 1/80 LD50). Results the obtained data showed marked changes in biochemical parameter, highly inhibition of AchE activity; highly significant increase in the frequency of micronucleus (PCEM) in rat bone marrow cells at all doses of fenitrothion alone or combined to vitamin compared to control group. Also, the histopathological examination of liver and kidney tissues revealed high alternation in these tissues corresponding to biochemical changes. Conclusion From these results we concluded that fenitrothion exert biochemical, mutagenic and histopathological effects in white rats. In addition, vitamin E has mild role in alleviating these toxicological effects
Screening for Common Mental Disorders and Substance Abuse among Temporary Hired Cleaners in Egyptian Governmental Hospitals, Zagazig City, Sharqia Governorate
RA Abbas,RAM Hammam,SS El-Gohary,LME Sabik
International Journal of Occupational and Environmental Medicine , 2013,
Abstract: Background: Informal employment is common in developing countries, including Egypt. This type of employment may have significant consequences on mental health. Objectives: To determine the prevalence and risk factors of common mental disorders and substance abuse among temporary hired hospital cleaners. Methods: A cross-sectional study was conducted on 242 adult temporary cleaners and 209 permanent cleaners working in 4 governmental hospitals in Zagazig City, Sharqia Governorate, Egypt. All participants were invited to complete a structured questionnaire through a semi-structured interview which included the self-reporting questionnaire 20 items (SRQ-20) and the work stress scale. Assessment of drug use included urine-based screening tests for common substances abused. Results: The prevalence of job stress, common mental disorders and substance abuse, particularly tramadol and cannabis (Bango), was significantly higher in the studied temporary cleaners compared to permanent cleaners. Risk factors associated with increased susceptibility of the temporary cleaners to common mental disorders were family history of substance abuse, high crowding index, history of physical illness, low educational level, and smoking; while being unmarried, male sex, family history of mental disorder, age ≥40 years, smoking, and length of service ≥8 years, were associated with substance abuse among the same group. Conclusion: Temporary hired hospital cleaners suffered from impaired mental health more than permanent cleaners. Therefore, expanding the coverage of current laws and occupational safety and health standards to cover workers in the informal sector especially in developing countries is recommended.
Genotoxicity among Hairdressers and the Level of Commitment to Occupational Safety Measures at Beauty Salons, in Zagazig City, Egypt  [PDF]
Rehab A. M. Hammam, Nanees S. E. Ghareeb, Manar H. M. Arafa, Hebatallah H. M. Atteia
Occupational Diseases and Environmental Medicine (ODEM) , 2014, DOI: 10.4236/odem.2014.22003

Hairdressers are chronically exposed to several occupational hazards during their work including potentially genotoxic chemicals. Hair dying, hair smoothening and straightening products are hazardous chemicals that affect human health and are frequently used in beauty salons. So, this study aimed to evaluate the genotoxic risk among the studied hairdressers, to estimate the level of p-phenylenediamine (p-PDA) in urine and to assess the degree of adherence of the studied hair- dressers to occupational safety measures at work. A comparative cross sectional study was carried out on 40 hairdressers working in beauty salons in Zagazig city, Egypt and 40 administrative staff at faculty of medicine as a control group. The results of the study revealed a significant increase in mean concentration of urinary p-PDA as well as significant increase in DNA damage assessed by Comet assay in lymphocytes among studied hairdressers than among their controls. Also, there was a statistically significant decrease in adherence to most of the occupational safety precaution measures that should be followed by the studied hairdressers. The significant risk factors of high Comet total mean score among the studied hairdressers were occupational use of hair straightening ≥8 times/week, use of hair dyes at work ≥15 times/week, length of service ≥13 years, negligence of wearing gloves during work, use of bleaching agents ≥12/week and negligence of hand wash after handling chemicals. So, it was concluded that the hairdressers are occupationally exposed to the risk of genotoxic hazards from chemicals frequently used in their work. The lack of commitment to occupational safety measures at beauty salons like wearing gloves during work and hand washing increases the risk of genotoxicity.

Studies of the Genotoxic and Histopathological effects of the Organophosphorous insecticide 'Profenofos' on white rats
Fatma M. Hammam* and Eman M. Abd el Mottaleb
Egyptian Journal of Hospital Medicine , 2007,
Abstract: Genotoxic effects of agricultural chemicals are of special concern because of their generally irreversible effects and the long latency associated with their manifestation. These effects include heritable genetic diseases, carcinogenesis, reproductive dysfunction and birth defects. The present study was carried out to investigate the effect of the organophosphorous insecticide "profenofos" on white albino rats. The rats were treated for 28 days with three different doses of profenofos (1/20 LD50, 1/40 LD50, and 1/80 LD50). Then the animals were left without treatments for 14 days for possible recovery. The genotoxic effect of the pesticide was evaluated by using the micronucleus assay in the bone marrow and polymorphism of glutathione S-transferase (GST) by polymerase chain reaction (PCR). The results demonstrated that the treatment with profenofos caused a significant increase in the frequencies of micronucleated polychromatic erythrocytes. Results of polymorphism of both GSTM1 and GSTT1 showed positive genotype in the control group. While the results of GSTT1 polymorphism in the treated rats showed positive genotype in all doses of profenofos. The GSTM1 polymorphism showed positive genotype in the high and medium doses (1/20 LD50 and 1/40 LD50) but not in the low dose (1/80 LD50), where the GSTM1 was null (negative) genotype. After the recovery period the polymorphism of GSTM1 and GSTT1 was found to be positive genotype, except with the low dose (1/80 LD50) showed null genotype for GSTM1 gene. The histopathological data showed that profenofos exhibited histopathological changes in liver, kidney, spleen and tests. Liver showed hepatic cell damage with degenerative changes. The kidney showed heamorrhages, edema, necrosis and glomeruli shrinkage. The spleen showed slight deplesion of the lymphocytes of the white pulp. The tests showed interstitial edema and severe necrosis of spermatogenesis. From these results we concluded that the profenofos exert genotoxic and histopathological effects on albino white rats
Analysis of Material Behavior for Friction in a Nozzle for Turbomachinery and High Speed Vehicles  [PDF]
S. M. Prabhu, Abbas Mohadeen
Materials Sciences and Applications (MSA) , 2011, DOI: 10.4236/msa.2011.210200
Abstract: Shock-induced separation of turbulent boundary layers represents a long-studied problem in compressible flow, bearing, for example, on applications in high speed aerodynamics, rocketry, wind tunnel design, and turbomachinery. Experimental investigations have generally sought to expose essential physics using geometrically simple configurations.
Thermal and Mechanical Modeling of Fluid and Heat Flow in a Porous Metal Using Neural Networks for Application as TPS in Space Vehicles  [PDF]
Prabhu S. M, Abbas Soundarajan Mohadeen
American Journal of Computational Mathematics (AJCM) , 2011, DOI: 10.4236/ajcm.2011.12015
Abstract: This paper contains novel model using feedback neural networks for a work piece temperature predic- tion.The heat and mass transfer in a porous metal workpiece which is heated by a fire gun is studied. The heat flux distribution is determined by thermocouple connected on the workpiece at definite distances. The gun work piece distance were also change and the temperature distribution and heat flux were determined. The permeability’s were in range of 0.01 – 0.15 .The ANN model parameters of the result output were simu- lated using the ANN parameters The simulation was done using MATLAB 6.0® Neural Network Toolbox.
Influence of Ca Content on Binding Energy and Cooper Pairing in Y1-xCaxBa2Cu3O7-δ Compound  [PDF]
Bassam M. Mustafa, Abbas H. Rostam
World Journal of Condensed Matter Physics (WJCMP) , 2015, DOI: 10.4236/wjcmp.2015.51003
Abstract: In this research, the influence of calcium content on the binding energy and Cooper pairing is investigated for the high temperature superconducting Y1-xCaxBa2Cu3O7-δ compound where x = 0 - 0.2). This is done by using model considering that the formation of Cooper pairs happens during tunneling mechanism of holes between the two CuO2 layers in the YCBCO crystal which are considered as forming adjacent potential wells. In this work, we make some modifications on the mentioned model and a modified equation for the binding energy as a function of Ca concentration is formulated to study the effect of Ca content by considering the change in the distance between the CuO2 layer as a function of Ca. The calculated results agree very well with experimental results. This happens because the Ca2+ substitution for Y3+ leads to decreasing the distance between the two CuO2 layers and hence potential energy of the system will be decreased. This leads to decreasing the binding energy between the Cooper pairs, and decreasing the distance between the two CuO2 layers increasing the tunneling probability of holes between the two CuO2 layers and thus increasing conduction mechanism and thus increasing current density, but this will decrease the energy gap and as a result decrease the critical temperature. The calculated results agree very well with experimental results.
Comparative Study between the Elastic Nail versus Hip Spica Cast in Early Treatment of Pediatric Femoral Shaft Fractures  [PDF]
Rebar M. Noori Khaffaf, Abbas Hasan Altaweel
Open Journal of Orthopedics (OJO) , 2016, DOI: 10.4236/ojo.2016.69034
Abstract: Introduction: Femoral shaft fractures are among the most common pediatric injury, which have the highest incidence among other pediatric fractures, and treatment of them carries a lot of controversies. Aim of the study: To compare the outcome of fixation of femoral shaft fracture by elastic nail with Spica cast. Patient and method: This prospective comparative study was carried out in Sulaimani Teaching Hospital, in the period from the 10th of December 2011 to the 10th of June 2012, for two groups of children whose ages were between 4 - 12 years (average 6.61 years), sustained traumatic femoral shaft fractures with follow-up period of about 6 months. The first group was consisting of 30 children treated by Elastic Intramedullary Nail, while the second group was consisted of 30 children treated by hip Spica. The selection was made on random bases. Results: Age range was between 4 - 12 years and showed male predominance in both groups with ratio of about 2:1 while fracture site showed predominance of the midshaft pattern in both groups. This study showed highly significant deference (P value of 0.001) between the two groups (Spica group of 3 days versus Nail group median of rate 4.5 days) in the admission period. Our sample showed shortening of about 2 cm in 2 case in the Nail group (6.7%) versus 6 cases (20%) in Spica group. We reported 4 cases of wound infection (13.3%) and 4 cases of pin site irritation (13.3%) in nail group. A higher rate of malunion was observed in the Spica group (10 cases more than 10° angulation in coronal plane) while the Nail group reported 2 case more than 10° in coronal plane. The mean operative time for Nail group was 55 minutes while in Spica group was 30 minutes. We reported shorter time to start mobilization and walking with support or independently in the nail group (weight bearing time 7.2 weeks) compared with the Spica casting group (weight bearing time 7.5 weeks). Conclusion: Elastic nail fixation yields better outcome for femoral shaft fracture in form of easier child handling, parent’s satisfaction, and maintaining acceptable fracture alignment.
Limitations to the determination of a Laguerre-Gauss spectrum via projective, phase-flattening measurement
Hammam Qassim,Filippo M. Miatto,Juan P. Torres,Miles J. Padgett,Ebrahim Karimi,Robert W. Boyd
Physics , 2014, DOI: 10.1364/JOSAB.31.000A20
Abstract: One of the most widely used techniques for measuring the orbital angular momentum components of a light beam is to flatten the spiral phase front of a mode, in order to couple it to a single-mode optical fiber. This method, however, suffers from an efficiency that depends on the orbital angular momentum of the initial mode and on the presence of higher order radial modes. The reason is that once the phase has been flattened, the field retains its ringed intensity pattern and is therefore a nontrivial superposition of purely radial modes, of which only the fundamental one couples to a single mode optical fiber. In this paper, we study the efficiency of this technique both theoretically and experimentally. We find that even for low values of the OAM, a large amount of light can fall outside the fundamental mode of the fiber, and we quantify the losses as functions of the waist of the coupling beam of the orbital angular momentum and radial indices. Our results can be used as a tool to remove the efficiency bias where fair-sampling loopholes are not a concern. However, we hope that our study will encourage the development of better detection methods of the orbital angular momentum content of a beam of light.
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