Ewas A.M.,Aljouf University |
Hamad M.A.,Tanta University
Ceramics International | Year: 2017
In this work, we studied in detail the magnetocaloric properties of La0.67Pb0.33MnO3 according to the phenomenological model. Based on this model, a large magnetic entropy change has been discovered in La0.67Pb0.33MnO3 when subjected to low magnetic field variation of 0.05 T. Furthermore, the results of Co doping clearly indicate that the magnetocaloric effect in this system is tunable. Therefore, this tuning makes this ceramic series potentially practical for the improvement of multimaterial layered magnetocaloric regenerators. © 2017 Elsevier Ltd and Techna Group S.r.l.
Fraihat S.M.,Aljouf University
Green Processing and Synthesis | Year: 2017
Green, sensitive and selective spectrophotometric methods were developed for the determination of nitrite in water samples. The methods (A, B and C) are based on the reduction of 5-nitroimidazoles; metronidazole (MTL), secnidazole (SCL) and tinidazole (TNL), respectively, followed by diazotization using nitrite in acidic medium, then coupling with pyrogallol (PG). The amount of nitrite was determined by measuring the absorbance of the colored product at 385 nm. The new methods were linear in the ranges of 2.5-30 μgml-1, with detection limits of 1.4 μgml-1. © 2017 Walter de Gruyter GmbH, Berlin/Boston.
Germoush M.O.,Aljouf University |
Mahmoud A.M.,Beni Suef University
Journal of Cancer Research and Clinical Oncology | Year: 2014
Objectives: The present study was designed to investigate the possible protective effects of berberine against cyclophosphamide (CP)-induced hepatotoxicity in rats. Methods: The experimental rats were treated with berberine orally at a dose of 50 mg/kg for 11 consecutive days after the administration of a single intraperitoneal dose of CP (200 mg/kg). The hepatoprotective effect of berberine was evaluated by assaying liver function markers, the pro-inflammatory cytokine tumor necrosis factor alpha (TNF-α), antioxidant defense system and gene expressions of both TNF-α and cyclooxygenase 2 (COX-2). Results: The biochemical results showed that administration of CP induced hepatic damage associated with a significant increase in the serum marker enzymes aspartate and alanine transaminases (AST, ALT) and alkaline phosphatase (ALP), and a significant increase in serum total bilirubin accompanied with a decrease in serum albumin concentration. In addition, CP-administration induced oxidative stress in the liver as evident from the increased lipid peroxidation (LPO), declined glutathione (GSH) content and glutathione peroxidase (GPx) and superoxide dismutase (SOD) activities. Moreover, administration of CP was associated with a significant increase in serum TNF-α. Similarly, CP administration was accompanied by a significant increase in the mRNA expression of both TNF-α and COX-2 in the liver as indicated by the qPCR assay. Concomitant administration of berberine efficiently alleviated the altered biochemical parameters. Conclusion: Berberine showed a marked hepatoprotective effect against CP-induced hepatotoxicity through alleviation of the elevated serum marker enzymes in addition to its antioxidant and anti-inflammatory efficacies. © 2014 Springer-Verlag.
Badawy S.M.,Aljouf University |
Badawy S.M.,Cairo University
Green Processing and Synthesis | Year: 2014
Green synthesis and characterisations of silverpolyvinyl alcohol nanocomposite films for possible environmental and biomedical applications such as wound dressing have been investigated. The synthesis was carried out in water, in an environmentally-friendly solvent using ß-D-glucose as a reducing agent and in polyvinyl alcohol (PVA) as a bio-friendly polymer. The green synthesis approaches have advantages over conventional methods involving chemical agents associated with environmental toxicity. The formation of silver nanoparticles (AgNPs) was confirmed by X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX) and UV-visible spectroscopy. The antimicrobial activity of the synthesised Ag-PVA nanocomposite materials against strains of different bacteria such as Escherichia coli, Enterobacter cloacae, Klebsiella spp., Salmonella typhi and Staphylococcus aureus was studied.
Hilal M.A.,Egypt Atomic Energy Authority |
El Afifi E.M.,Egypt Atomic Energy Authority |
Nayl A.A.,Egypt Atomic Energy Authority |
Nayl A.A.,Aljouf University
Journal of Environmental Radioactivity | Year: 2015
The aim of this study is oriented to investigate the influence of some physicochemical factors such as radium distribution, grain size, moisture content and chemical constituents on releases of radon-222 from the accumulated phosphogypsum (PG) waste. The emanation fraction, activity concentration in the pore and the surface exhalation rate of radon-222 in the bulk PG waste are 34.5±0.3%, 238.6±7.8kBqm-3 and 213±6.9mBqm-2s-1, respectively. These values were varied and enhanced slightly in the fine grain sizes (F1<0.125mm) by a factor of 1.05 folds compared to the bulk residue. It was also found that release of radon from residue PG waste was controlled positively by radium (Ra-226), calcium (CaSO4) and strontium (SrO). About 67% of radon release attributed to the grain size below 0.5mm, while 33% due to the large grain size above 0.5mm. The emanation fraction of Rn-222 is increased with moisture content and the maximum emanation is ~43% of moisture of 3-8%. It reduced slowly with the continuous increase in moisture till 20%. Due to PG waste in situ can be enhancing the background to the surround workers and/or public. Therefore, the environmental negative impacts due to release of Rn-222 can be minimized by legislation to restrict its civil uses, or increasing its moisture to ~10%, or by the particle size separation of the fine fraction containing the high levels of Ra-226 followed by a suitable chemical treatment or disposal; whereas the low release amount can be diluted and used in cement industry, roads or dam construction. © 2015.
Shaltaf S.,Aljouf University |
Mohammad A.,University of Jordan
International Arab Journal of Information Technology | Year: 2013
This research introduces the hybrid Multilayer feed forward Neural Network (NN) and the Maximum Likelihood (ML) technique into the problem of estimating a single component chirp signal parameters. The unknowns parameters needed to be estimated are the chirp-rate, and the frequency parameters. NN was trained with several thousands noisy chirp signals as the NN inputs, where the chirp-rate and the frequency parameters were embedded into those chirp signals, and those parameters were used as the corresponding NN output. The NN resulted in parameter estimates that were near the global maximum point. ML gradient based technique then used the NN output parameter estimates as its initial starting point in its search of the global point parameters. The ML gradient based search improved the accuracy of the NN parameter estimates and the new estimates were very much near the exact parameter values. Hence it can be said that NN working in corporation with the ML gradient based search results in accurate parameter estimates for the case of large signal to noise ratio.
Akbar I.,Aljouf University
Journal of Clinical and Diagnostic Research | Year: 2015
Introduction: The restoration of posterior teeth with composite restoration is a common clinical practice nowadays. Opinions regarding posterior composite restorations vary among dentists. The aim of the present study was to determine the knowledge and opinions of general dental practitioners towards composite resins for posterior teeth restorations. Materials and Methods: A questionnaire was devised to elicit information regarding placement of composite restoration in posterior teeth in northern Saudi Arabia. It was distributed to 230 dentists by hand and e-mail. A response rate 136 (59%) was obtained. The questionnaire sought details about case selection criteria for composite restoration, problems associated with composites and reasons for selecting composite restoration in posterior teeth. The data was processed and analysed by SPSS statistical software 19. Frequencies and percentages were calculated for various responses of the participants. Results: Regarding the selection of composite restoration in posterior teeth, 97% of the dentists did not prefer composite placement for class I restoration with heavy occlusal contacts. 83% of the participants did not select composite for class II restoration. 78% of the respondents opted for restoring composites in small defects. Patients’ aesthetic demands (90%), amalgam replacement (22%) and restoration of endodontically treated teeth (42%) were the contributing factors. Regarding the problems associated with posterior composite restorations. Recurrent caries (87%), post-operative sensitivity (84%), restoration fracture (83%) and polymerization shrinkage (73%) were the major problems reported by respondents associated with composite restorations. The other minor concerns were wear (60%), contact build up in case of class II cavity restorations (51%) and isolation for composite restorations (36%). Conservative cavity preparation (78%), aesthetics (73%) and patient preference (65%) were the main reasons for choosing composite restoration for the posterior teeth. Conclusion: Posterior composites are not popular among dentists practicing in northern Saudi Arabia and there is a need of continued professional education and clinical training for the dentists for posterior composite restorations. © 2015, Journal of Clinical and Diagnostic Research. All rights reserved.
Ahmed O.A.M.S.,Aljouf University
Acta Mathematica Scientia | Year: 2012
This article has two purposes: the first is to give some structure results for the class of m-isometries, and the second purpose is to extend the notions of left and right inverses to m-left and m-right inverses respectively. © 2012 Wuhan Institute of Physics and Mathematics.
Akbar I.,Aljouf University
Journal of Clinical and Diagnostic Research | Year: 2015
Objectives: Flare-up during root canal treatment of non vital teeth is a common clinical incident. The aim of the present study was to assess the effect of prophylactic use of antibiotics to avoid flare up during root canal treatment of the teeth having asymptomatic necrotic pulp. Materials and Methods: A randomized double blind clinical trial with parallel design was conducted on 100 subjects with asymptomatic non vital teeth. They were randomly divided into two groups. The first group (50 participants) was given two gram amoxicillin one hour before the first visit of root canal treatment; the second group (50 participants) did not receive any treatment (control group). In both groups, root canal treatment was performed in two visits. The flare up was assessed by the pain visual analogue scale and based on the swelling criteria. The data were processed and analyzed using SPSS statistical software 17. A p-value of 0.05 or less was considered statistically significant. Results: A total of 80% of participants in the experimental group had flare up while 12% of participants had flare up in the control group. Prophylactic Amoxicillin had no effect on inter-appointment flare up (p > 0.05). There was no relationship between flare up and patient’s age, gender and tooth type (p > 0.05).Conclusion: Prophylactic use of Amoxicillin in asymptomatic non vital teeth before root canal treatment had no effect on the incidence of flare-up. © 2015, Journal of Clinical and Diagnostic Research. All rights reserved.
Al-Zarea B.K.,Aljouf University
Medical Principles and Practice | Year: 2015
Objectives: We evaluated the maximum occlusal bite force (MBF) among individuals with fixed partial dentures compared to the opposite dentate side and determined the relationship between MBF and gender, age, and body mass index (BMI). Subjects and Methods: A total of 85 subjects (43 males and 42 females, age range 28-66 years) with fixed partial dentures on one side and dentate on the other side participated in the study. The MBF was measured at the first molar area on both sides using a digital hydraulic bite force gauge. The highest MBF value was recorded from three measurements of bite force at each side (with 45-second intervals between measurements). Results: The mean MBF was 596.2 ± 76.3 N at the dentate side and 580.9 ± 74.3 N at the fixed partial denture side. The difference was statistically significant (p < 0.05). The MBF values were greater in males as well as in taller and heavier participants. Nevertheless, the BMI had no relationship with MBF values (p >0.05). Conclusions: Within the same subjects, the measured MBF values at the dentate side were higher than those at the fixed partial denture side. Females, lighter, and shorter participants had lower MBF values. Meanwhile, the BMI had no significant relationship to MBF values. © 2015 S. Karger AG, Basel.